As far as increasing the amount of ejaculate, the biggest contributing factor is genetics (which you have no control over). Orgasms in males occur due to a spinal cord reflex that causes strong rhythmic contractions in several parts of the urogenital system. Ejaculation is governed most strongly by contractions of the urethra, prostate, and the muscles at the base of the penis.

There are various methods that people use to increase the amount of their ejaculate. Probably the most popular is that of Kegel exercises. At the simplest, you contract and relax the muscles throughout the day. You can locate these muscles by stopping your urine mid-stream. These are the muscles you want to strengthen. After a few months, you should notice stronger, more powerful orgasms and ejaculations. While this won't actually increase the volume, per se, it will make it appear like you are ejaculating more.

As far as increasing your sperm count a good sperm enhancer like Maximum Pills can ensure that you are maximizing your sperm count.