A quick smooth way to tame a diplo is to have a small taming pen, make the kibble needed before hand for a passive tame. Then have it agro onto you since it does no damage you don't need to worry about it hitting you. Lure it into the pen and just lean against a wall of your pen and just let him constantly push you. You won't actually move and it saves a lot of kibble and time to passive tame rather than KO.
For anyone that wants to passive tame it here is an area under it where he will play the push animation but it wont actually push you this leaves you only with the annoying rawring to deal with for more than 10 mins