As an SA user, it's actually easier for me to attack it while it's charging for about 5 seconds, then dodge twice out of the way.
A lot of it's moves are very telegraphed, especially it's tail-spin and backflop attacks, which are avoided easiest by dodging towards the Zin in most cases. It's arm pounds are avoided in much the same way. If you land under it's chest, you take no damage, and since it overcompensates it's lunge towards you, by dodging forwards it will reliably miss you and bring you right into attacking range.
Evasion as a skill is also awesome. Then again, it's like, one of the best skills anyway \:D/
It lets you dodge roars, avoid attacks and keep up the pain with ease.