Cool! I’ve been seriously thinking about doing this too, and have researched it extensively, so here’s what I know:
First of all, are you white or black or any variant in between? Because if you have traditionally “black” or Asian hair, it dreads easier. If you’re white, it’s best if your hair is thick and/or curly.
Second of all, the common misconception is that people with dreads don’t wash their hair. This is false. Most people wash their hair every other day or so. The trick is not brushing or combing it. You wash it as usual, then let it dry naturally without combing or brushing it.
It takes longer if you’re white, even with thick hair. I have a friend who is half-Filipino, half-white, and it took him about two years to get full-on dreads. Curly hair helps too. It tends to look really ratty on the in between stage, but after a while it looks great. My friend Joe is white, with curly hair, and it took about three months for the dreads to kick in. My best friend Gladys is Filipino and she went a month without combing it, and now it’s all dreaded, so YMMV.
There are some great products out that help you get mock-dreads so you can try them out. TiGi Bedhead is the best stuff (kind of expensive, but worth it). I can’t remember the name off the top of my head, but it’s molding cream. You just twirl a cunk of hair and then run the stuff up and down it, then blow-dry it. It takes a while, but it will give you an idea of how it look on you.
Finally, when you get sick of it, you have to cut it all off - there’s no in between.
If you try them out and like it, invest in some cute caps and head wraps to hide the in-between stage. Of course, I’ve seen people who look awesome during that stage; I think I would just look unbrushed.
I’m still debating whether I will do it. I love the way it looks, and recently cut off all my hair (it’s a chin-length bob now), so it would be pretty easy, and my hair is curly now that it’s short, and very thick. I think maybe this summer I’ll stop combing it.