More information about Watling Gardens and a map can be found here.

Walk 3 minutes up Shoot-up Hill after turning left out of Kilburn Tube Station. The Watling Gardens Estate is on the left, almost opposite St. Cuthbert's Road.  Or you can travel by any of  these buses:

Bus stop

Walk on to the estate, through the entrance from where you can see the little playground, then walk past the playground:

 Watling Gardens Tower

Go to the left of the block with the white panel and a yellow sign showing "WATLING GARDENS 97/135":

Nearby block

 

Just beyond and to the left of that black notice:

WG

 

Walk just beyond the small black notice on the LEFT of the picture:

 

Left

Now you can see the door.

 

 

And you can see the sign (though it doesn't show up so well when it's dark); open the door and come in:

sign

And the room looks like this:

Meeting room inside