I made this mistake the first time that I tried to tame an equus. You have to stay mounted or else you will loose taming effectiveness.

be prepared to get Dizzy when taming the Equus

You can feed it then use a bola (which doesn’t lower effectiveness) and after that use fence foundations and walls to keep it in place and ride it for the duration of the tame. No need for it to run around randomly.

Mount it fast when the first feeding or you'll be done

TAMING STEP BY STEP:
1. Get your carbemynous( did I spell that right? ) and look for rocarrots(eat jungle ferns)
2. Once you have at least 30, go to south zone 3.
3. Look for the cliff and walk along it.
4. Once you see the lake thing, look for an equus.
5. Once found, look out for dilos, rexs, and theziosaurs.
6. Tame.
Ps: Can be ridden without saddle.