If you are new to a server and you have some materials. The easiest way to tame a Giga is go to swamp and use a good berry gatherer to gather the bushes. The bushes are very close together. You will get lots of narcoberies. Then, ask the admins for biotoxin and Giga taming will be in the bag. If you want to be safe stack 10-15 large bear traps on each other when you trap it. Gives you plenty more time.
I dare you to raise one!! They are savage if you got two high lvl parents (about lvl 140ish) and you get imprinting on it. The thing will become an adult with about 230% melee and basically one chomp any bronto!!! But on the down side you loose your job and your girlfriend
Make 4 metal dino gates and 1 large bear trap. Place three frames and door into an incomplete square and the large bear trap in the I between them. Lure the Giga into the trap and while its trapped place 4th down to make the square. Then just light it up with tranqs