ok, this is off memory - we managed to back track a very similar route too.
Theres a road that goes off downhill away from smarts r us - behind it, houses and stuff down there. Went down there, and then right. Found a pub called The Phoenix, then went left - past a school (arnold view?), and then turned right, up some big hills, down some big hills. Then found a kinda mainish round, so turned left onto that - then wondered down there, i remeber passing a Conserative Party place, BP garage, and a tesco. Kept walking. Remeber a shell garage (smart has to run on optimax, so we keep an eye for them!). Came to a split in the road, i think it was called medway, or something similar, slung a right and carried on walking. Then it became more city centre like.
Return was pretty much the reverse, just a few minor diversions on residential streets. Was a good walk.