First, go to the Dasher Online Demo. If your connection is slow, you might want to download the software and install it. even if your connection is fast the online demo can get sluggish a bit. The demo is mainly for the curious.
Step 1: Clicking stops and starts Dasher. The red line is the vector. The speed is controlled by controlling the length, the direction by changing the angle of the vactor.

Step 1
Step 2: “Drive” the vector towards the letter you want next. When you get closer to a letter it increases in size. Like magic, Dasher predicts the next letters you may be looking for and also spaces. Just go with the flow, think about what you are trying to write and let Dasher do the work.

Step 2
Step 3: When you get to a word that isn’t in Dashers dictionary, you might have some trouble. Just Dasher will do its best to help you but will also stay out of your way. I believe after using an unusual word once, Dasher adds it to the list so that prediction improves later on.

Step 3
Step 4: You will notice colors are helpful in Dasher. When you need a comma, period of other puctuation, aim for green. When you need a capital aim for yellow. For everything else colors just make it easier to distinguish what you are aiming for.

Step 4
Conclusion: The guy who came up with the idea for Dasher is a freak’in genius! His name is David MacKay. The group of people who made Dasher what it is today are also very awesome.