Some "before painting" questions;

I prefer to mask open gear bays, bomb bays etc by filling them with toilet tissue. If any area needs particulay coverage, I may wet it to get it to comform. Inner faces of doors and such are easily masked with a piece of masking tape.

For canopies, my current method is masking it first, then attaching the canopy, and finally painting it in place.

On painting itself, work from lightest color first to darkest last. Paint the outline of the color first, then fill in the center on each following color. Or you can mask for a hard edge pattern.

For the bays I sometimes if possible I blue tac the doors over the space and use it as the mask or use some expandable foam like the stuff ear plugs are made from.

As for canopies I usually mask it off after a dip in future. (Tape is last thing off when model is done)

Tempararily stick it in place with white elmers glue.

Paint inside frame color first on the canopy.

Paint the entire thing from Lightest color to darkest as mentioned before.  

the last two replies.

I built that B-1 years ago and decided to free hand the camo -- it's so big and I got the AB to a fine line that it looked perfect.  Then filled in the color with a larger spray pattern.  The model is long gone after 3 coast-to-coast moves or I'd send a photo. 

By installing the canopy prior to painting you can fair it in for a more realistic look.  Remember to paint the canopy (after masking) to the interior color first, then camo.  After final sealer of dull coat on top of the weathering/decals then the tape comes off.

Tim