After login by entering correct credentials you will visit your facebook profile very first time. You need to setup profile by following these steps:
1- Most important is to add profile picture. Make sure to put nice picture as it will be public and everyone around the world can see it. Click on add photo and browse picture from your computer and choose any.
2- Similarly do this for setting the wallpaper or cover photo of your profile. It is also public and everyone can see it.
3- Next step is to start adding friends so that you can contact them and do some chit chat 
