The ta field sign is part of the woL path route? Which combines at times with the sustrans Glasgow route. At the start at tan field probably just take the road to Stockbridge? Cycle through to St Bernard's well then round behind the gallery of modern art to to roseburn. Can b a little wet. From there cycle though murrayfield to the jenners depository and then up the tram Tarmac and out the stenhouse path then jink up to the canal towpath at cultins road. Take canal to Herriot watt, cut through the university out the west gate then dependent on where you want to end up in Balerno take the road to Currie and up the a70 or the backroad to ravelrig hill. Lovely climb right at the end?
If stats dry and woL path stops being muddy from roseburn you can get round to slate ford and up the bike chute to the aqueduct and then tow path for one kilometre then you can take the footbridge on to the woL path.
Basically you have options dependent on how much rain has fallen. Up hill probably about an hour as quite a few fiddly bits