Another friend of mine recently started practicing with my Naginata club. Because the club meets only once a week at most and she sometimes has trouble understanding the other members (they speak mostly Japanese), she bought a naginata and I teach her on the days that I don't practice with my students. It's really nice because I have to go slow again and it gives me the chance to really pay attention to my form.
One day last week my visitation school's Naginata club didn't meet, so I was able to use the dojo (and its nice big mirrors) all by myself. It gave me the opportunity slowly run through all of the strikes and blocks for engi (forms) and realize just what I didn't know -- when I practice with others I rarely have the time to really stop and think about what I'm doing. I didn't know quite where my hands should be on some of the blocks, so I asked during the next practice and now I know!
But I still sometimes get confused by different sempai (people who have been practicing Naginata longer than me) telling me different things.
I've never been light on my feet. I remember being a little elephant in my ballet class when I was six years old. But I'd like to be more nimble before I start doing shiai (sparring), so I bought a jump rope with bearings. I jump on days that I don't practice with students and use a simple free app on my iPod to keep track of the jumping/rest intervals. Right now I jump for 45 seconds and rest for 15 seconds for a total of 20 minutes. As I get better the jumping interval will get longer and the rest time shorter. Bonus: it's also a good cardio workout!
I found a good glossary for Naginata terms. I like it because it includes kanji (the thousands of Chinese-derived characters that standard Japanese uses). So now I can easily cut-and-paste the kanji to get the pronunciation in hiragana (a much more simple syllabic script that is also used for some types of words in Japanese) instead of looking at it in a book and laboriously selecting radicals on WWWJDIC! (See my post about Naginata terms in hiragana.)
I finally figured out how to do a few things! One was how to keep the back creases straight when lying my hakama (pants) flat back-side-down. I pinch them together at the bottom with one hand while holding the top with the other hand. The sides go down floppy but I can straighten them out before I start folding. And I figured out how to wear a tenugui, which is kind of like a bandanna that you wear under your men (helmet). On previous attempts I was wrapping it around my head wrong so it wasn't secure. I also figured out how to get a little bit of baby powder out of the little container I carry it in without making a mess.
 For some reason the website says it isn't free, but it is.
 Now that it's hot and I get sweaty, I use baby powder at practice to keep my hands dry so they slide along the naginata instead of sticking to it.