rent a gate at all the London airports and setup routes to each of them. You can go up to 2 freq for these to utilize your plane and generate more revenue but not more than 2... start expanding outwards from london when you have the money-drop the freqs back to 1 as soon as you can (keeping your plane busy)... Lease aircraft to get you more and more revenue... Remember-at the beginning-the capacity of the planes is so small that you really don't need to go to the big airports yet. Go to the mid sized airports to save $$ so you can fly to more routes.
And welcome-soon you will be as addicted as the rest of us I'm sure!