Sump help

I just tore down my 60 gallon tank due to newbie mistakes. I am planning on making it right by redoing things. I want to add a sump, but im not sure what all i need, i have a 20 long that i can use for the tank, but other than that i am lost. i know i will need an overflow, but im not sure if the glass is tempered so I've heard eshoppes is the best to go for hang on back, i just really need some input on how to do it. i am looking for any designs so.. yup thanks for the help