Here is my step by step guide to becoming a lomographer..
1) Buy a holga 135 (alternatively you could be a holga 120, but 120 film and process is more expensive)
2) Buy some 35mm film, 200 if you're shooting in daylight, and 400 if you're shooting in the evening, 800 if you're shooting indoors... 1600 if you're shooting at night in geylang. Oh and you may want to try buying some slide film, then getting the photoshop to develope using normal process, which would result in crossed processed photos, neat color look, check out cross processed photos on flickr or google image search for more info.
3) after you install the film, shoot shoot shoot... don't think just shoot
4) Develop the film, and examine the photos. Find out which photos you like, and then ask yourself why you like them. Once you've decided WHY you like the photos, start trying to take more photos like that. By your 3rd roll of film you should be thinking about WHY/How, because the first two rolls would have given you some things you liked. By your 5th roll of film you should be shooting photos you like without even thinking.. if your keeper rate is above 50% you're doing well, if it's below 50% you should go back and repeat step 4..
5) Buy more wacky type lomo nonsense cameras and experiment. Perhaps move up to 120 film and cameras by that point, if you're actually printing larger prints... Else stick with your 135 because it's cheaper.
Best,
Adam