In case you don't know, privacy settings are accessed from the drop down on the top right of your screen when logged into Facebook (see image on the left). This mostly applies to finding and tagging. I will show you how to make photos and your "about" area private later.
On the following screen, I recommend choosing the Custom option on the far right (see below). I initially had mine set at "Friends" but I don't like what it did with my photos: if I tagged one of my friends in a photo, his/her friends could see it and comment on it.
Under Custom, you can uncheck the box in front of "Friends of those tagged" to avoid the situation described above.
How You Connect is a key area to check out. Change all of these to Friends, and Friends of Friends for friend requests if you would like. This makes you ungoogleable, so the only way people can find you is if you are in their friends' friends list.
The second option from the bottom under Privacy is to "Limit Audience for Past Posts." You may want to consider this if you have previously had a public profile. It will change every past post to Friends only.
So, that's pretty much what you can do under Privacy settings. Not too helpful, right?
Here's how to restrict visibility of your Info or About page.
Go to your profile (or timeline, I guess it's called) and click About.
You will need to click edit and check out every area. Yippee! Get yourself a cup of coffee and do some clicking. You will want to see the icon on the right, which means friends only. Below is a screen shot of one part of mine. I haven't filled in most of it, but everything is set to Friends only anyway. You can tell something is set to Friends only at a glance because it has that image of a person behind another person. Make sure to save it.
Then, you have to manually change all of your photo albums to Friends only, or at least check what they are set at. I wasn't lying when I said Facebook does not make this easy. First get to the page with all of your albums, so go to your Timeline and click on Photos which is right below your cover photo. Cover photos are public and that can't be changed. The world symbol on the bottom right means public. You can see most of my albums are Friends only, but there are some that have this star with spokes or something (Mobile Uploads, Wall Photos, and Year in Status Photos has this). Those mean I need to choose my audience for each photo. Thanks Facebook. My default was friends only (not sure how that happened), but I could see this being a hassle if they are not. If it happens that you need to change every photo, you could create a new album, move them all there, and change the privacy on the new album. I think Mobile Uploads have that setting automatically. I remember once moving my Mobile Uploads.
I think that's everything. When you are done, you can go to http://www.facebook.com/about/control and view your profile like the public would. You will need to be logged into Facebook to try it. Please let me know if there are other easier ways to do this or if you run into any snags.