Keep your drawings loose
Work fast and efficiently: keep your drawings loose and fluid so you don’t get bogged down in detail. This will enable you to move through your scene quickly without losing momentum. However, ensure volumes and anatomy stay consistent! I love the feeling of the hand-drawn line. Some may prefer a crisp edge, but this isn’t the time for it. You can clean up your drawing afterwards.
Flip your images
When working in traditional animation you would flip back and forth between sheets of paper to see if the movement was correct. Working digitally, you can achieve this same effect (and more) with the Onion Skin tool. The tool enables you to see each drawing or frame overlapping the previous and next ones. Make sure you continually use it to maintain consistency.