Hmm, for starters with her coat I would simply brush out the dead hair and undercoat with a slicker brush and shedding blade. When you brush her out, mist her coat lightly with water. Brushing a slightly damp coat is easier and more comfortable for the dog than brushing a totally dry coat (especially around here where I live, as it's so dry. The dogs get static-y!) Unless her fur is really dry and "open", I wouldn't shave her. Border Collies' coats are great insulation and once they are shaved, that special coat will never grow back the same way.
I would personally get her a "cool coat" to help her cool off. You soak them in water and they maintain at a certain temperature. Dakota has one that he wears to trials and I imagine he would have died without it by now. It works wonders; he doesn't even pant in 100 degree heat, in direct sunlight.
As for trimming feet, it really takes some practice. For starters, you don't CLIP feet. Don't take electric clippers to any part of the foot but the fur between the pads. When you trim the pads, use a #30 or #40 blade (some people use a #10 or #15 but I prefer not to as it is WAY too easy to cut the dog's tender skin using longer blades) and do a sort of "scopping" motion with the clippers. Don't press down hard on the clippers but don't be afraid to dig out the hair.
Dakota's feet need to be trimmed soon so later today or tomorrow I will get you a few pictures of what I do with his. It's hard to explain without showing photos. Maybe that'll give you a better idea of what to do with Tippy's....