Once the cycle ends and ammonia and nitrites are 0 and nitrate is near zero or at it then you can add your cleanup crew which usually consist of snails and hermits(variety is always good, but dont get turbos, too big for small tanks like yours and mine). Then i would wait at the least two weeks or even a month before adding a single fish. Im adding two clownfish so they will pair and it will be easier but usually you should add just one fish and let the system stabalize. After the first fish is added i would wait another 2-4 weeks before another. Your max is probaly 2 fish, maybe 3 but i wouldnt do it unless they were small. I would also suggest you to set up a Quarantine tank. Mine that i setup was a ten gallon i had laying around in the garage with a heater and sponge filter. Its lighted by a reg desk lamp(lighting really isnt an issue). You dont need to QT the cleanup crew so you have some time to get the stuff togather. Im also just getting into this hobby so if someone who has more experience is welcome to correct me if im wrong.