If you shave your beard, you'll look ten years younger.

Literal

Beard shaved [conditional-たら] 10-years [topic-は] rejuvenated appear [emphasis-よ].

髭剃ったら is the casual たら conditional with を omitted. 若返って見える means 'to look rejuvenated.' 10歳は uses は for emphatic minimum — 'at least 10 years.' Very natural casual speech.