I got through 12 lessons this way, stopping at prepositions (postpositions?) as it introduced a little too much at once but I felt like I was making real progress. At this point, I started looking around for more learning resources, and found a few useful thing, but all signs seemed to point in one, very scary, direction: Learn Hiragana. Truth told, this hurdle always seemed to be the bridge too far; "There's so many characters", "The symbols are so complicated", "It'll take too much time/effort" my most common excuses. But this time... this time, I was determined and I stumbled on this wonderful post: http://www.tofugu.com/2010/10/13/hiragana-guide/
I learned 10 Kana (Japanese characters) that night.
(Yes, my handwriting is awful, shush)
This morning I immediately went and reviewed what I'd learned... and it had stuck! So I learned 10 more!
At this point I've gone through 30 Kana and since, at least at this point, it seems to be working, I'll outline my process for learning them. I start with 10 character blocks (but you could take it down to 5 easily enough) and move one character at a time.
I've been using Master Hiragana course over at http://iknow.jp because I like the pacing and interface and was recommended by the site I mentioned earlier (also it has a free trial that I'm still on), but you could use anything that will show you an individual character, speak the character and show you the stroke order.
In any case, for each new character, I say it aloud, and then write it down 10 to 20 times, saying it aloud each time to associate. After each one, I'll move to another page, and write down each character I know so far, up to and including the newest one, once each (again, reading it aloud) to re-enforce.
After each set (again, I've been doing 10 to a set, but 5 works too), it's time for an exercise. The goal of the exercise is to be able to blindly associate the Kana with the sound in a random order. The re-enforcement step above is helpful, but it quickly becomes a pattern. You don't want to remember that ki is き simply because it comes after ka か, (that'd be like needing to sing the alphabet to remember what letter G was), so you need an exercise to break the pattern.
Luckily, there are lots of tools available to that end. The best ones are probably the worksheets available from that tofugu post. They challenge you to first take the Kana and write out the English syllables, then to take the English syllables and write the Kana. An effective strategy, and it has you writing them more which is good for muscle memory and improving your handwriting.
Some other useful tools for these exercises:
A Hiragana Drag and Drop This one has you drag the symbol from the pool at the bottom to it's syllable box above. Pretty good.
A Customisable Random Speed Quiz Select one or more sets of characters and it'll show them one at a time forever. Type in the syllable to move to the next one. As a bonus, you can select up to like 8 fonts and it'll select a font at random for each character, keeping you on your toes. Fantastic.
Anyway, that's where I am right now. My current goal for tomorrow is to finish out the remaining 16 of the 46 base Kana, and Dakuten characters. I'll close this with a couple more links to useful resources.
http://www.textfugu.com/ An amazing Internet Book for learning Japanese. The first "Season" is free and includes fundamentals and learning Hiragana.
http://ankisrs.net/ A super handy flash card study app. Available on all platforms for free, including mobile!