How about looking at some nice landmarks in North London
1- Elstree Lake
2 - St Albans Cathedral / city
3 - Old Leavesden aerodrome (NW Watford)
4 - Hatfield
5 - Lea Valley resorvoirs
6 - M25 Motorway
Suggest you plan a local solo flight using these features in your plan and fly in your armchair the night before. Back it up with a bearing on LAM VOR or BPK and you should be able to extend your knowledge and confidence of the North London area without too many prob's
In that area though if "unsure of postn" for more than a couple of minutes then get straight onto 121.5 or Luton / Thames radar as appropriate and "confess"
Good Luck !