Ambiguity of the Profile Photo: Photo to display at the top of your profile and the Site Picture: User icons . Profile Photo is not mentioned at all, and it should be clear that these photos are not interchangeable. Clarify the difference of the two will be helpful. Site picture can be changed without changing the profile photo. The main purpose of the Site Picture: User Icons are used to show it with your name when leaving comments, etc.
Changing your Site Picture
"2. Click the link Change Site Picture" Delete the word "link" to unify the whole document; it is the only place you wrote "Click the link", and everywhere else it has been "Click the ...."
"Your Site Picture is a 100x100 snapshot.." Delete the words "100x100." Simplify as a "small" maybe? It makes sense to include the pixel size description in the step 3. "The site will automatically shrink..." and is clear here.
"Hint: OSOQ.com" section breaks the flow of the tutorial content, and should be after the "4. Name your picture" as a side note.
Adding Widgets to "Personalizing" your profile would be helpful. I suppose you can just create a link to the Adding Widgets in the Communities section? It is ambiguous whether the Widgets can only be applied to the Communities or can be applied to Profiles too.
Access Restrictions
Define "Public Access and Private Access." Is the Public Access as in it can be searched on internet search engines such as Google? Is "Private Access" defined as the user's friends? user's connections?