There is a couple of weeks in the very beginning where the time taken between forming one chord and forming the next is just too long. The solution is to keep trying the changes over and over again until the fingers just go to the right place automatically.

The good news is there is no secret to it (since you are teaching yourself, you might think you are missing something) the bad news is there is no secret to it (it just takes time).

Hope that helps. Keep at it! :)

Jon