On the advice of this board, I bought some 0.25 Retirides on a recent trip to Spain. How do I use it? I know to apply it at night, after cleansing, only every 3 days or so (I'm a regular retinol user), but what else can I use with it, if anything? Can I mix in some skin oil like I normally do with my night cream? It sounds like it will be drying. Can I use eye cream? A hyaluronic acid serum before or is that a no-no? I also know to use SPF the next morning. Thank you!