Explaining the process is difficult, your best bet would be to find a knowledgeable person in your area to demonstate. Sanding grit will be determined by how large of a defect needs to be removed. For major major texture problems some people start with 600 or 800 grit then step it down to 1200or 1500, 2000, 2500, 3000. If the paint went on good with just some minor peel then you may want to start with 1500 grit. The finer the grit used the less chance of a cut through and the easier it will be to buff. Sand a 2ft square area then squeegee the water off and check, when all the texture is gone move over and do another area, repeat. When you're done sanding one panel buff it with compond and move to the next- the clear buffs easier imediately after sanding (if it is still green). The slower the buffer turns the less chance you will burn the paint. 3M's perfect it 2 and 3 are good compounds, there are many good compounds available. Whenever possible use a backing pad when wetsanding, I use a thin piece of rubber, some prefer balsa wood. Straight sanding strokes, no circles, and change stroke directions when stepping down to a lighter grit- you will then be able to see when the cutting is done and it will sand faster.
Colorsanding and buffing is best explained and demonstrated in person IMO. I bet the video mentioned would be good.