Baker Street platform numbering is:
Met main: 1 (bay on Chiltern Court side), 2 NB, 3 SB, 4 (bay on signal box side)
H&C/Circle: 5 EB, 6 WB.
And the Yerkes tube we generally don't mention within the same breath as the Met
.....
Bakerloo: 8 SB, 9 NB.
Jubilee: 7 SB, 10 NB.
For the unintiated LT refer to their lines as North, South, East or Westbound rather than the traditional railway 'Up' and 'Down'.....
...unless it's the old GC and Midland where I believe historically they travelled 'Down' rather than 'Up' to London. I think there is still a 197 milepost on the ex-GC line just south of Harrow as the GC measured their distances from Manchester.
A map found on t'interweb and finally for a bit of triva, Baker St has the most number platforms (10) of all the LT stations.