I recently asked a similar question about practice and got some good feedback....search my screen name on this forum to find it....only a couple of weeks old...
As said, 14.1....also, work rotation games with 3, 6, and 10 balls....work on 8-ball break and run-outs.....also advise working on your banks, I often leave these out in practice and being confident banking is a big plus....I've actually come up with a practice rountine, nothing special, but it gives me a start...
Warm-up...pick a shot a work the different types of english, and try to work the ball to any position on the table....use short from 99 critical or other book if needed....
9-ball break, remove bottom 6, race the ghost to 5....in 9-ball, always try be on a 3-ball plan, recognize tough balls and clusters early....
9-ball break, remove bottom 3, race ghost to 5
10-ball break, race ghost to 5
14.1, race to 100, record high runs
8-ball, race ghost to 5
Short banks, race ghost to 5
Not all need to be done in one session.....I warm-up with one shot because many gave advice that it's really tough to just practice....I threw in the games because it makes it fun for me....also, make sure to play people, don't just bang balls around by yourself all the time.....play some one-pocket if you get a chance....learn as many games as possible...