Go here to sign in and edit your profile.
Note: Students cannot register for accounts, and can play with PhET simulations without registering. Educators should register for an account in order to download teacher-submitted activities, access teacher tips, or watch teacher primer videos. Register for a free educator account.
You can resend the email confirmation here.
Sometimes, the confirmation will be marked as "spam" or be filtered by your email server. If you do not receive the second confirmation, try whitelisting "[email protected]" and resending the confirmation above.