If you are playing solo and haven't hit a shot since the ace then you
should be on the scorecard screen. Near the bottom right of the
scorecard click on the button labeled Replay Shot. After you click the
button you'll see your avatar setup for the replay. Click the SAVE button at the bottom.
If you have already advanced past the scorecard screen (but still haven't hit a
shot) then click on the MENU button in the top left of the game and
choose REPLAY LAST SHOT. You'll see the SAVE button at the bottom once the replay loads.
If you've already hit a shot then there is no way to save a replay, but you can try to save the scorecard. Instructions on how to save a screenshot to your PC can be found in the first 4 steps of this post.
Good luck and congrats on the ace! =)