A good way or my way of taming a giga

First, get a ascendant Longneck.

Second, get some tranquilizer darts.

Third, get 4 metal gates to trap the giga and some bear

traps.

Fourth use soothing balm if your on mobile.

Fifth, use an argy to find one ( they usually spawn up in the mountains or on flat surfaces in the mountains

Sixth, use prime meat, Queztal kibble ( on mobile ) or, regular meat.

And abracadabra you have your self a giga Goodluck on trying this method.