Hello, your username and password it is only required if you try to sync the notes between multiple computers/OS/browsers. For example you can create a sticky on firefox at home, then go to work and find the same sticky on your chrome browser on a mac. If you do not register it won't be possible to sync the two computers.
If you do not need the sync simply disregard the note and you will be able to use OurStickys without any problems.

The login is also necessary if you have a software that might clear your cache and background activity once in awhile. Being logged in will re-download the stickys that you have saved (backed-up) and restore them at the first login or page load.

Please be aware that OurStickys does NOT store any of the personal information, the login it is only used to gather your email address and associated it to your account, everything else that might be sent from the 3rd parties is disregarded.