Don't worry 90% of young people get spots at some point and they are unfortunately part of growing up. They are due to hormonal influences. The important thing to remember is that they will go, so be patient.
Spots are a result of hormonal changes during puberty.

Here are some methods you could use to try and prevent spots:

MEDICATED FACE WASHES
These are better than ordinary soap for cleansing your skin as they remove spot-causing bacteria more effectively and avoid over drying. Most are developed for the more delicate skin on your face.

MEDICATED LOTIONS
These serve as a good substitute for regular lotions since they also contain anti-bacterial ingredients. They unclog pores by removing the daily build-up of grease and dirt, in some cases twice as effectively as ordinary cleansers.

MEDICATED PADS
These are a convenient cleansing alternative. They are usually pads that are pre-soaked in anti-bacterial solutions. Not only do they cleanse the pores, they leave behind anti-spot ingredients to help prevent new spots appearing.

If you have moderate or severe acne you should make an appointment at your doctors for treatment