Ok no rocket science
1. Two (2 watts per gallon of fluorescent light) on a 20 gal that's 40 watts.
2. A decent substrate, like fluorite which can be mixed 50/50 with gravel.
3. A reliable source of Carbon. Seachem Excel
3. A reliable source of Trace Elements like Seachem Flourish
4. Hearty
low light plants like Anubis etc.
5. Dechlorinate tap water with the following ranges...
KH min 5
GH average
A moderate fish load and food used to supply NO3 and PO4
Immaculate house keeping!
Vacuuming and water changes at least once a week. Min. 25%
There it is, a complete guide on to how to be incredibly successful with aquarium plants, in less than a paragraph. I am good, very good

Lol.
Jay