I really love beautiful chalkboard writing, but my own efforts so far had been really disappointing! I did a bit of reading online, and decided to try some chalk/pastel pencils.
Here you can see the difference between using an ordinary chalk and using pencils!
I bought a couple of different pencils from Cass Art (and would have bought another from Paperchase if the person serving me hadn't dropped it on the floor - and she didn't even understand why I thought this was a problem!). The white pencil is a Cretacolor chalk pencil, and the blue one is a Stabilo CarbOthello.
The chalk pencil was a huge improvement on chalk sticks, but I discovered that the CarbOthello pencil goes on much more smoothly than the chalk pencil and doesn't wear down as quickly. It also seems to erase quite well. Now that I know the sort of pencil I like, I am making a list of all the colours I want to buy!