Can i tell me how i can prevent some bruises from forming on my face?

Arnica: Since you're talking about prevention, I assume it's before a procedure or injection. You can take oral arnica before the procedure to help prevent bruising. You can also avoid aspirin, ibuprofen and similar medications and avoid alcohol for 1-2 weeks before your injection, as these will increase bruising. You can also ice right before the injection to shrink the blood vessels.