Instead of trying to memorize what you have you should be thinking about what you NEED.

Example you hold A2KQ, with the Ace suited in hearts. You look at your cards and don't need to look at them again becasue you are thinking I need low cards, Hearts or Broadway cards.

Another example:
You hold 569J, you look at your cards and should be thinking, How the hell did I get in this hand?

Be thinking about what you need, not simply what you have. If you need to look back to check or be sure I don't think it's hurting you.