First, welcome aboard! In the Aux there are two types of office you can hold. One is appointed Staff Officers for particular areas, at different levels (flotilla, division, district, national in order). The other is elected, which is generally administrative (again at all those levels). Each level has different stripes or "A"s. Appointed are red, elected silver.
In general you are going to need your first year just getting through basic instruction and passing required exams before moving into a staff position. That also depends on how big your flotilla is, and where. We are up in D9, so weather and ice keeps us from getting underway 6 months of the years. If you are in the Keys, then you have more time on the water.
The publication you want is the Auxiliary Manual. Google COMDTINST M16790.1G which is the Commandant's Instruction Manual for the Aux.
Hope this helps.