from someone who has coordinated multiple cross country transports for animals, heres some advice -
first, we need to know starting town and ending town. if you feel uncomfortable stating your hometown,then pick one nearby. that way people interested in helping can see what an approximate route is.
second, make up legs to the transport using major breaks, i try to keep most legs 1-2 hours, otherwise people get tired and dont want to do all the backtracking.
third, we need to know what the animal is travelling with. has it had all its vaccines? how does it ride in a car? does it come with a crate if it needs one? some people dont want a strange dog (potentially puppy) loose in the car if it may have an accident, so they need to make plans. is the dog microchipped? healthy?
that's just a start...