Click on Log in on the upper right hand corner of the website, and then on Forgot Password? Enter the email address associated with your account. This is the email you used to sign up with or the email associated with your Google/Facebook login if you used that to sign up or the email you entered to complete your profile when you signed up using your cell phone number. The password reset link will then be sent to the email.
Please note that multiple log in attempts with the wrong password or email will lock you out for sometime.