The details of my walk to Edinburgh -
I actually started this hike at Keswick and followed the Cumbria Way to Carlisle, then hiked east along Hadrians Wall to where the Pennine Way crosses over (just before Housesteads) and then hiked north to Kirk Yetholm. Once there I followed the Scottish National Trail (St Cuthberts Way forms part of the route) to Melrose, onto Peebles, onto West Dean and then down into Edinburgh. The Scottish National Trail web page has very clear OS maps, descriptions, and mileage about the trail route in Scotland.
Or of course, the other option would be to start in Edinburgh and walk south. At the time my son lived in Edinburgh (he has now moved South) so it made sense for me to walk to him and then catch the train home to Portsmouth. I could have flown to Southampton but I couldn't get a reasonable cost fare.
If I was to hike the route again I would start in Edinburgh and walk south, for me it would be like walking towards home. Hopefully, then I might get a cheapish flight up and would try to finish at the southern end of the Cumbria Way. I must admit I really liked the walk, each named hike section had its own charm, demand, and interest. The only boring bit is that section from Carlisle to Dalston but its soon over with. With me, as always, the most physically demanding bit, especially in bad weather, is from Kirk Yetholm to Byrness.