All I did to tame mine was:

Get my sarco boi

Get narco, meat and tranqs

Find spiney boi and take them to a river

Swim around in circles on your sarco

When you are far away, shoot them with tranqs

Repeat until their knocked out,

Feed them food and use your sarco to fight off any dinos

Then go back home

You need a high level sarco bc mine 44 and can kill Anything ;-;

Hope this helps! ^^