Sometimes I feel like a bit of a novice myself, but here are some tips to start with:
Learn the fundamentals. Try drawing cubes, boxes, cylinders etc. to get the hang of basic forms (you'll need them.)
Drawing from life helps immensely with learning the characteristics and proportions of an object you want to draw, particularly humans and animals, probably the most common. Studying, possibly copying the work of masters (that exist out there in the field of pixel art as well) helps as well. There are some tutorials in the
Tools, Resources and Linkage topic that will get you started, and, as always, here's
another I usually refer to.
But remember that this won't happen overnight, or even the course of a few nights!