Two ways come to mind:
First, you could add a transition to your workflow that allows you to move the file back to ther state it was in before you submitted it for approval. If any transition actions or revision incrementing happened upon submittal, they will have to be undone. I have such a transtion in my workflow, and I call it 'Recall'.
Second, you can use the Rollback function in the History dialog to roll the file back to the version prior to the submittal. Note that this will undo any changes that happened during the original transition (transition actions, revision increments, etc).
If you aren't an admin, you may not be able to do either of these things yourself.