Elastics are really good for dreads, they help the dreads form the way you want them to and keep loose hairs in. And if you palm roll them while you have them in it will actually dread the hair.

Conditioner will always lubricate the hairs and loosen the dreds, because that's what it's supposed to do.

Of course you can wash dreads, actually dreads tighten faster when they are clean, so the more you wash the tighter your dreads will become.

You should make a habit of washing your dreadlocks every 3 days, but really, you can wash them as often as you like, but you should wash them at least once a week.

It's a good idea to use a shampoo that doesn't leave anything behind when you have dreads. It is more important to use a shampoo that doesn't leave anything behind when you have dreads rather than when you just have normal hair because dreads hold a lot of stuff that usually falls out of normal hair when you brush it. The stuff will build up in the dreads and will cause the dreads to break down, loosen, and fall apart.

Some shampoos can be really bad for dreds because they leave residue behind on the hair, which can lubricate the hairs and cause the knots to fall apart. Residue is not a problem for normal hair because normal hair is straight and free flowing, whereas dreads and braids are a little harder to rinse well because they hold residues much easier because of the way it is tightly packed together. The residues can also cause itching and irritation on the scalp because they build up and the scalp cannot breath.