Washing dreadlocks is more important than you think...
Unless, of course, you think it's really, really important...
In the first three weeks your dreadlocks be will very delicate and you'll want to wash them either every 3 days or every 4 days. Pick one and stick to it for the first month. The consistency will help your scalp adjust. If you are washing them every three days your first washing will be three days after you put them in etc.
After they have had a chance to establish themselves a bit, usually by the start of the second month, you can begin washing them every other day or every second day. You can continue that schedule for the life of the dreads. If possible, always use residue free shampoo when you wash your dreads. Not only will it help them mature faster, it will ensure that new growth continues to lock up and that they continue to dry quickly. Soap residues slow down and in some cases prevent the hair from locking properly. Residues can also build up inside dreads, increasing the time it takes for them to dry. This can eventually lead to dread rot (mildew growing) inside the dreads. Growing mildew is unhealthy and it smells like you're wearing a sour gym bag on your head. Fortunately it's easy to avoid! See the info about getting your dreadlocks dry in our FAQ.
You can keep use a dreadlocks washing cap to protect your dreads while you shower for the first month or so. Yeah, I know you'll look a little ridiculous but it keeps the delicate new dreads together better during washing. Pour some soap on your head, and lather it up through the cap, then rinse it out really well. If you have rubber bands at the roots and tips wearing the washing cap is less necessary as the bands help keep them together pretty well. More on using Using Rubberbands later on...
After you wash your dreads, squeeze and shake the extra water out in the shower. Squeeze them again grabbing them with your towel over your hand. Continue this until most of the water has been squeezed out. Put them in a dry towel (one that doesn't shed) while you get dreads. Squeeze them again with the towel over your hand to get some more water out. Finally you can use a hair dryer to dry them well. Later when your dreads mature you'll find that using a hair dryer is more and more necessary. Squeezing them with the towel really helps get the water out of thick dreads, as does slinging them a handful at a time. If you leave them to air dry the rest of the way make sure they are not tied up and make sure the majority of the water is already squeezed out. Never stick your damp dreads in a tam and leave them there.
Probably the most important maintenance you can do for your dreads is to get them good and dry after washing them. It trumps pulling in loose hair and clockwise rubbing every time. Why? Because letting your dreads sit wet leads to dread rot and dread rot is the reason many people have had to cut their dread journey short - literally. Yes, keeping dreads free of soap residue is a big deal, it will put you in control and you'll be able to get your dreads dry in a reasonable amount of time. Unfortunately, if you leave them sit wet, you're still not out of the woods. If found that a hair dryer can make the difference between leaving them "wet n drippy" or getting them dry enough they'll never have a problem, and it can do it fast.
I've gone through my share of hair dryers in search of one that deserved the title of "Dread Dryer". After a lot of experimentation it became obvious what makes a good dread dryer. It needs to have a heat setting that doesn't roast your dreads and it needs extra powerful fans. Blowing air through a dread is no easy task. I've also found that the right diffuser can prevent the dyer from overheating while making the shape of the air wider and much better for drying dreads.
You can find the dryer I use here. It's pretty bad ass for a pink hair dryer (it just looks red in the pics). Multiple fan speeds and heat settings, dual fans, a diffuser, turbo, It's like the sports car of dread dryers. =] It was only about $10 more than a cheap-o dryer and it's saved my dreads from the rot monster more than once. Why? Cause it gets dreads dry fast!. I've also been testing dryer caps, you know, those things you put on your head that dry your hair/dreads from all sides... I some trial and error I found a cheap one that works great. This particular Dryer Cap will slip right over the diffuser attachment on the dryer I mentioned above. The problem with many of these caps is that they slip of the dryer or don't fit at all. This combination works really well. Use the highest fan setting with the turbo, and the middle heat setting. It's warm enough to dry fast and it won't scorch you or your dreads. You can wear it on your head or you can put longer dreads in it like a basket and let them sit beside you. Nothing dries those tips faster!
Now that your dreads are nice n' dry you'll notice all your rubber bands will have slid up a little, towards the tips. You'll also notice a bit more straight hair at the roots. Washing tends to help the knots move around and this can leave more un-knotted new growth at the roots. Fortunately this is a great time to clockwise rub and make knots. As you check each dread to see if it needs clockwise rubbing you can also slide back any bands that have rolled up the dreads.