If you've got some time to spare I'd recommend looking at some of the articles on Paula's website.
If you live in Arizona...well...honestly if you live anywhere the sun comes up I think the first and foremost never-miss-it product you have to use 365 days a year is sunscreen.
And yes, for sure, retinol in any form will make you more sensitive to the sun. So you'd want to be thoughtful about your sunscreen.
In response to the advice to get prescription Retin A...this is fine if you can tolerate it. I went that route - tried every.single.different.way to apply it and I just could NOT tolerate it. For those who can...go for it! Great stuff.
As far as exfoliation...that too...every day (again if you can tolerate it). Chose the type based upon your skin concerns. Mostly sun damage and wrinkles? Try alpha hydroxy acid. Got blocked pores or acne? Beta hydroxy acid.
I exfoliate every day. I use alpha hydroxy acid although I have blocked pores because, again, experimentation shows me I can't use beta hydroxy acid.
Oddly enough I can manage a little bit of the BHA 9 just under my eyes though for my milia.
The Paula's Choice customer service is terrific and I'm sure they'd be happy to help you build a simple starter routine.
*I don't work for Paula's Choice...I just love her products and philosophy and am so glad they're bringing back the radio show!*
OK...I could go on and on....I'll stop here.