Mine is to create a circle of wall around the area. Whats your tactic?

Defend: Find a wide, open area near the flag that people usually travel through, and make a giant bridge across it, making it a choking point. Takes a lot of time and getting shot at, and doesn't net you many kills. But if you're interested in wins and like conj, it's a great way to be annoying distract the enemy; time is on your side as defender after all.

Both: As soon as round starts, go to other side of flag that enemies always walk through, and dig a hole down, and then shot op (away from flag) to make it wider. This causes a lot of people to fall down and not know how / not bother to get out. This gives your team the high ground, and also makes it so the opposing team has that many few people who cluster in the flag.

Attack: either create a "circle" around it once it's taken, or if there's a corridor nearby fill it up to create a choke point.

Edit: typo

Attack: i tend to really like to do air shots especially when its an open map and no conjs in the sky yet.
Defend: i take it very seriously when it comes to defending the flag or vip. on vip maps ofc i would stick with the vip like glue
unless the vip can take care of herself/himself flag maps: rush to the flag start making a fort around it kill anyone who tries to
attack the flag and protect it till most of our team is protecting it.

Either wing it or wait it out.

Defend: surround area + spas camp
Attack: Just spas camp.