The first step to do a planted tank is to decide what plants you want to go for. Each lighting level will have different needs for a tank. Take a look at AquariumPlants.com
to research some plants that you like most and then you can go from there.
For low light plants you can get away with stock t8 lighting without having to worry about ferts.
Medium light level you will need to upgrade to a stronger lighting system and start supplementing with ferts and a carbon source.
High light level is more difficult and will require more care to get growing correctly without creating an algae farm. Fertilization is definitely required at this point.