Hi Matthew. If you use hot water for a minute or so to soften your stubble and use a gentle cleanser, or something like neutrogena skin cleaning shave gel, or even benzoyl peroxide face wash if you don't shave too often then you won't get spots. Use something like clean and clear moisturiser after wards. Always wash thoroughly and use cold water for a while after to close your pores.

No. Shaving does not cause acne. It is due to two things, mainly, bacteria and hormonal influences.
Use an electric razor instead of a blade. Apply a pre-shave oil before you apply shaving cream/foam. This will help reduce the friction on the skin. Jojoba oil is an excellent choice to help reduce friction and irritation.