{I'll need firm directions as I'm not the best person for finding my way around.}

Hi Bez,

Travel details from Slough - Golders Green as follows....

Slough - Paddington
Paddington - Kings Cross/St Pancras (Circle/Metropolitan [clockwise/eastbound])
Kings Cross/St Pancras - Golders Green (Northern Line northbound [Edgware Branch]).

Hope this helps

Speak soon
Ken.