That was pretty tough to watch
The big points of focus for you, IMO, should be:
Stabilization
Framing
Cuts
Stabilization is the obvious one, the shake in that edit was pretty rough, and made me not want to keep watching. A tripod is a must. If you don't have the money for a nice tripod, use a crappy one and create movement in your shots with framing and editing.
When you are filming and editing, be mindful of everything you are doing. Instead of just standing on the side and pointing the camera at the subject move around, try out different angles, different heights, high, eye level, low. See what these do to your footage, what effect does the different angle have?
Look at the way that the subject will be in/move through the frame. Is that the best way to do it? Will it look the way you image? If not, change it.
In your edit the riders heads, arms, whole body, etc. would get cut off. That is something to avoid, unless you are using it to some effect. In some of the shots the cut off parts were so bad that there was no reason to keep the shot
With your editing you need to do the same thing, pay attention to everything you do, because each little part builds to create the edit as a whole. The song is very important, it will set the mood of the edit. In picking a song you need to make sure it will flow with the riding and the editing in order to create that mood.
In selecting the shots that you put in, only choose the best ones, short and sweet with only good shots will be way more powerful than a longer edit. Each shot in the edit should serve a purpose, if you are on the fence about including a shot, or not, leave it out. That edit shouldn't have been more than about a minute.
When cutting the shots, think "why should I cut it here? Why not here?" what will an extra second, 3 seconds, etc. of this shot do? The cuts in that edit were way too long. If you lose the subject in the frame, cut it, don't wait til you find the rider again.
Cutting with the beat of the music really adds to the overall flow of the edit. It creates a great opportunity for beginning, cutting, transitions, endings, etc.
...And i'm bored, but...
Sparknotes: be more mindful of all the little things
