I'm working on that too. I don't know if I'll ever just have one tab, but I've gone from tens to fewer than five. Just have to remember to bookmark.
I find bookmarks worse than tabs. Bookmarks are where things go to die and take up space. My current working theory is unless they are just links to sites you use everyday for work or whatnot, instead of bookmarking a site, do something with it, for example write a journal entry about the information on the site, or start writing a program and just link the site in the comments of the code if you need it for reference.
Bookmarks are a way for your brain to lie to you saying "ya, i'll get to that later, I promise."