Tips for cutting fabric on the cricut machine?

Hi I am wanting to try out some applique, and wanted to cut out shapes on my cricut machine. I have looked online for some tips or tutorials, but haven't really found anything.
I am wanting to know what blade I use, regular or deep. How fast I should cut, and what to set the pressure to.
I will most likely be cutting out thinner fabric, so I doubt I'll need the deep blade. Would I meed a new mat as well?
Any other tips would be wonderful!