There are Three modes for Shamans Normal or Hardmode or Divine

In order to be Shaman you need to wait till you have the highest score in the players list but not usually the first.
if you want to try to be Shaman you need to go to an empty room (/room "the room you want") and try to build by yourself, your goal is helping other mice to get cheese into the hole.
1.Normal Mode
in Normal mode you have all features that can help you and its saves count in the player's Profile in the first part
So you start with Summoning Plank with Nail (B) and make it Ghost (invisible) by space but you have to think about ways to put it in each map like:

As Nail B makes everything stable in its place on the map but doesn't make it in fixed rotation so, you should put it exactly on the ground like in this picture. Then connect to it Planks (or any other object) with Nail C you can change the position of nail C by pressing C 3 times. There is Also other Nails which are V, N, J
and Also you have spirit which gives a boost for mice in the direction you make it like :


2.Hard Mode
It is available to play with it after 1000 saves, in this mode your appearance change like the feather get twisted and some drawings on year get different but the most useful feature that you have the ability to make a totem! totem is a constant building you build by clicking the feather in your enterface then click "Edit totem", you can build unique useful totems that can help you in your Shaman's turn
Examples :

you put nails the way you want!
but you lose the ability to put Planks with B nail and you can't put spirit anymore!
the saves in this mode count in the second part in the profile

3.Divine Mode
This is the hardest Mode to play with as you can't use B nails nor C nails, and also you can't put spirit nor Totem you limited power but a large Range that can help you build with anvils and planks with the best way! (plus getting the best appearance with the shaman wings!) you can enable it after 5000 normal saves and 2000 Hard mode saves.
example on Building :

this mode's saves count in the third part in the profile

Basically the gameplay is so simple you have to know how to do your turn as a good shaman

so you have to Click on a certain object from the shaman objects and start holding the mouse on the position you want *inside the range* then poof! you put something

you can press F for additional note for your fellow mice

Skills can be a nice Features for any shaman to use them but Recently the Skills don't work in Vanilla rooms, you can easily choose your own skills by then
each time you level up you get the ability to select one skill from the skill tree

(this is my own strategy as i distribute the skill points 2:2:1 or 1:3:1 depends on the skill tree)
The Wildling and Physicist skill trees are unlocked after you have reached level 20.
you need to select skills wisely as you depend on them with your shaman's ability!
If you want to know about specific skill you can press Ctrl with F key and write its first word!

• Spiritual: Additional Time: Adds 5 seconds to each round(till 25 seconds) ,Big Cheese: make the cheese bigger till 10% (till 50%) ,Big Shaman: Increase Shaman's size by 4% (till 20%) ,Superstar: Dance and 1-5 mice around you will dance too ,Unburstable: you spawn again once!! after you die ,Easy Victory: you can make the mice enter the hole if they have the cheese and there 's someone already entered before!!!!! ,Ambulance: you can revive mice again from death ,Chief's food: you can give cheese to 1 to 5 mice if there is someone already entered the hole!!!! ,Anti_gravity: Make balls fall slower ,Teleporter: you can teleport 1 to 5 mice to your position,Speed Boost: can increase the mice speed used 3 times ,Apple: you can put anything in the apple's small range ,Ancestral Spirit: you can summon when you are dead for 5 seconds (till 20 seconds) ,Spring: can make mice bounce used 3 times ,Cloud: can be resummoned many times and it have fixed rotation but you can't use it in Divine mode
• Wind Master: Endurance: increase the speed by 4% (till 20%) ,Clean Mouse: A bubble come when a mouse die from 1 (to five bubbles) ,Cleats: Increase friction by 20%(till 100%) ,Diet: Decrease mass by 10%(till 50%) ,Opportunist: you enter the hole automatic after the last living mouse in the map enters the hole ,Chocokiss: From 1 to 5 mice kiss you when you sit ,Rocket Scientist: hold down key then jump for a high height ,Companion Crate: summons a heavy Crate that can be used in building ,Tight Budget: Summons tiny planks for 2 times (till 10) ,Personal Teleporter: teleports you to the certain position can be used 1 to 5 times ,Projection: gives you a dash *you can go through walls* when you click left or right key twice ,Transformice: you can give 1 to 5 mice the ability to change themselfs to temp.Shaman objects ,Stern Mouse: gives you 1 to 5 more ice cubes ,Acrobat: you can build while you move ,Angel: you can hover by holding up key!
• Mechanician: Big Spirit: increase the range of the Spirit's effect by 10% (till 50%) ,Multiple Balls: Summons 1(till 5) more balls ,Lead Cannonball: increases the weight of the cannonball by 20%(till 100%) ,Super Anvil: increase the weight of the anvil by 20%(till 100%) ,Ice Plank: gives you an ability to summon no-friction (ice like) planks with the texture of ice ,Aerodynamic Balloon: increases the speed of balloons by 10%(till 50%) ,Stable Rune: gives the ability to summon a fixed rotation Rune ,Chocoplank: gives you the ability to summon a high friction (chocolate like) planks with the texture of the chocolate ,Pre-inflated Balloon: gives you the ability to summon instantly balloons without even holding the click ,Master Summoner: increase the Summoning speed by 6%(till 30%) ,Anti-Spirit: when use space with spirit (ghost spirit) it attracts the mice to the ghost spirit ,Demolition Worker: gives you the ability to remove any Shaman objects in the map ,Architect: you can change an invisible(Ghost) Shaman object to visible object ,Sheep: when you spawn it explodes after 3 seconds (it can be used twice) ,Eagle Eye: increase the shaman's range by 30%
• Wildling: Campfire: makes you put campfire decoration for 4 seconds(to 20 seconds) ,Reflex: increases the Summoning speed, but decreasing your summoning range by 4%(till 20%) ,Small but Brawny: decreases the shaman's size by 4%(till 20%) ,Spidermouse: makes you summon spider web (which hinders the mouse movement) can be used 1 time (till 5 times) ,Earth Symbol: you can summon triangle object! ,Meep: you can give the meep ability to 1 mouse(till 5 mice) ,Go Through There: you can decrease the size of 1 (to 5) mice ,Nature's Return: remove every shaman object on the map! ,Thorns: increase the plank's friction ,Landslide: you can turn one cannonball into 2(till 6) smaller rocks ,Renewal: restore all the skills you used ,Leaf: you can summon it on a mouse to make him/her very slow (can be used 1 to 5 times) ,Evolution: summon it on a mouse to increase his/her jumping power (can be used 1 to 5 times) ,Gregarious Spirit: increase your summoning speed by 2% for each saved or dead mouse ,Shameow: gives you the ability to turn yourself into a cat (which have higher jump and walking speed) you can turn it off by pressing down key!
• Physicist: Anger: when you do the anger emote from 1 (to 5) mice around you will cry ,Recycling: you can remove 1(to 5) nails ,Antigravity: you remove any object's gravity can be used 2(till 10) times ,Rollout: you can make the mouse roll can be used 1 (to 5) times ,Solitary: you won't have soulmate in your shaman's turn! ,Stop!: use to stop the moving of all mice 2(till 10) seconds ,Restorative: makes the object on its fixed rotation no more jingling! can be used 1(till 5 times) ,Mad Scientist: you can shot cannons upwards! ,Gravitational Anomaly: makes the map with no gravity for 2(till 10) seconds ,Grapnel: used to hang you anywhere on the map can be used 2 (till 10) times ,S: you can summon S shaped object now! ,Booster: summon it to boost mice into specific direction can be used 1(till 5) times ,Handymouse: you can now connects two objects together can be used 2 (till 10) times ,Big Plank: you can now summon a very long Plank!!! ,Controlled Disintegration: when any mouse die it now puts a small trampoline that can help other mice to jump on it!

Credits:
Bishomilad
Fewfre's Transformice wiki which helped me gathering the information of the skills