Practice your ball control. Start by seeing how many times you can bounce the ball between all the men on any the three bar. You may only be able to bounce it a couple of times before losing it, but you'll soon get to 5 or 6 times, then 7 or 8, then eventually many more. Once you get your consistency on that bar, move to the five bar. The trick, especially starting out, is to let the ball bounce off the men without adding much extra power. This will improve your smoothness and enable you to more easily set up the ball for your shots. It also teaches hand/eye coordination which will help in all phases of the game. If you control the ball, you can control the game, even against someone with a superior shot. Ball control is also the one of the skills that translates from one table to the next best.
Try to find competition that is just slightly better than you. Eventually, you'll surpass them, then move on up to stronger competition. If you play against people a lot better than you, don't get frustrated. Keep in mind that in a 16 team tournament, there is 1 winner and 15 losers. Nobody wins them all, not even Spredeman. Just enjoy the game and strive to get better. The enjoyment you get out of the occasional win is the icing. The friends you make is the cake.