The most important thing you can do to reduce the signs of aging, is protect your skin from the sun. I’m sure your dermatologist says the same –
Ideally an SPF of at least 30 is the best, but even daily use of a SPF 15 product will help. You can use something straightforward from the drugstore, like Oil of Olay or Neutrogena.
I personally like LaRoche Posay, as my skin is a little oilier and some other products leave my face too shiny – then makeup melts off!
Here is a great local list of sunscreen picks.
Enjoy the sun!