Know that it is easiest to passive tame them, which means walking up to them and feeding them
Get a TON of berries, everytime you feed it, it will go up like 3-5%
Have a high speed, high attack flying dino, (high attack in case you "miss click")
HAVE PATIENCE, diplo's are a stubborn tame, they will push you playfully (hence the flying dino)
MAKE SURE there are no carnivores around, if there are carnies around it will attack it there is a chance of it dying, it will get rid of all your hard work, and most importantly, IT MAY DIE (R.I.P. attempted tame #1 + 2 😢)
Plz note I am not an "high level player" that has a giga, I am lvl 50, (51 at the time I wrote this, almost 52) so I am not that experienced, tho I am sorta, I don't know that much about the game
Passive tamed a level 12 (+5 levels) with 15 mejoberries. If you can situate yourself under it’s legs, specifically between the two front ones, the diplo will continue to try and bump you back but will be unsuccessful. It will do this move over and over again, and drain its stamina and hunger faster, which leads to a faster tame.
Whoever said tame by standing between (or just behind) front legs, is very much right! Just be careful not to get attacked or let it get attacked by some other raptor or something. Reset the tame meter.
KEEP IN MIND! If you dare to breed these... the babies eat TONS of berries QUICKLY! Put probably a couple thousand berries in its inventory and it might last you a bit...
If you want to take it, get a ton of berries and walk under it. There is a spot under it were it keeps attacking you but cannot hit you. If you find this, look straight up and feed. It doesn't move and can't hurt you
These things are easy to tame, just get TONS of berries (or kibble) and walk right under it, then it cannot sweep you off a cliff. Make sure that there are no carnivores around to kill it. If you do not have some kind of gun and you are low level use a pter