Yes! Once you can easily retract your foreskin (pull it back) and see the head of the penis, it is time to start washing underneath it. NEVER force your foreskin back.
Smegma
Smegma is a naturally occurring lubricant that allows the foreskin to pull back.
Washing Foreskin
People with a foreskin need to wash underneath it, everyday, to remove the build-up of smegma. Here is how:
Gently slip the foreskin back in the shower.
Use a mild soap and warm water to wash the head of the penis and inside fold of the foreskin.
Rinse the area well.
After the shower, pull foreskin back to dry the head of the penis.