When you are on the ground, you have three options:
1) Try to get up
How to get up from the mat: To get off the mat you need to stand up. If you’re on the bottom, get yourself into a better position, like guard or half guard. If you don’t see a get-up option from the position you’re in (especially on top), try pressing L1 to bring up the advanced options.
Risk: You get denied, and your opponent gains a grapple and stamina advantage over you.
Benefit: You get up and are no longer in a bad position on the ground.
2) Try to submit your opponent
How to submit your opponent: You need to get yourself into a position where submission is possible. From there hold down LT and your submission options will appear on the HUD. Initiate the submission by pressing the right stick with LT held, in the direction corresponding to the entry on the HUD.
Risk: You get denied, and your opponent gains grapple advantage stamina advantage over you. Or, your opponent escapes your submission and you end up in a worse position.
Benefit: You submit your opponent and win the fight.
3) Try to reverse positions with a sweep or reversal so you take the more dominant position
How to sweep your opponent: In order to perform a sweep, you need to get yourself into a position where a sweep is possible. Guard is your best option. Once you are in a good position, hold down LB and your sweep options will appear on the HUD. Initiate the sweep by pressing the right stick with LT. You can also sweep your opponent by performing a reversal when your opponent tries to transition. Reversals are performed by denying your opponent’s transition very early in the animation. This can typically only be done if you anticipate their action and are ready to act quickly when you see the animation start.
Risk: You get denied and your opponent gains a grapple and stamina advantage over you.
Benefit: You gain a dominant position and can attempt to work for a finish from the top, or get up easier.