Yoga. If you have an Xbox etc or a pc with speakers torrent some non workout purpose yoga and just do it at home. I didnt believe in yoga, I do the slowest yoga workout ever and it had dropped my weigh, increased my grappling strength felxability etc hit all the muscles that no other workouts have except wrestling and Jiujitzu.
I wrestled and I reccomend it.
Also, for abs specifically, I recommentd inclined/ hanging abs with a medicine ball throwing back and forth, passing back and forth, slamming the abs.
In 2 months, you would be as ready as necessarry.
On the off chance hatha yoga is not enough, do power yoga, you will die.hatha yoga great for getting your gappling muscles begun Power Yoga, you will not survive
If you do not torrent, just download the utorrent client software to start, it is worth it for all the books and videos avalable for learning all things.