[ORAS] Any tips for ORAS?

[DrLems]

So this will be my first Pokemon game since Pokemon black on the old DS, im getting my first 3ds on the 28th with OR is there any tips about anything that will help me out along the way like

"Don't faint "certain" Pokemon because you cant get again"
"Save before doing this.."
"Get money by.."


Anything really that will be helpful :D Thanks