Sequence for painting windows
Paint each of the window sections first, leaving the frame until last.
Start with the glazing bars.
Then paint the hinge edge if it is an opening window.
Move to the top and paint the top rail.
Next, paint about about a foot at a time alternately down each of the vertical side rails continuing all the way down.
Next, paint the bottom rail.
The frame can then be painted.
If you have a frame with intermediate uprights, paint these first.
The rest of the frame can then be painted as a continuous length.
Finally, paint the sill board starting with the underside of any overhang and finishing with the top surface.