Always paint the ceiling before walls or woodwork.
As long as you don’t have a lot of furniture to clamber over, painting a ceiling is fairly straightforward.
Firstly sheet up everything which is in danger of getting paint on it. No matter how careful you are, paint splashes have a way of finding exposed surfaces.
Use a stepladder, preferably one with a platform to hold tools or a paint container. If you haven’t got steps, strong plastic milk or beer crate or a wooden chair should be adequate.
The golden rule, whether using proper or improvised scaffold, is NEVER to over-stretch.
If you are right-handed work from right too left and vice-versa.
Painting a ceiling is easier if you use a roller, unless the ceiling is very small in a cupboard or toilet, especially with artexed or wood-chipped ceilings any ceiling with a rough patterned surface).
When painting with a brush, use a large flat brush 6 to 8 inches wide.
You can also use a small brush 1 to 2 inches wide to get into corners,
Cut along the edge of the ceiling and for cutting round the light rose and any other awkward bits.
Starting in one corner on the window side of the room, paint in sections about 2ft square.
Work across the ceiling doing a strip at a time.
When using a roller it is a good idea to use one with an extension handle. Most roller handles have an open end into which you can push an old broom handle, which will do the job.
Using a small brush (about 2″ size will do) cut in all round the edge of the ceiling and round the ceiling.
Starting in one corner roll about a Metro Square and work across the room in strips the same as with a brush.
If you are using a long handle on your roller it means your paint tray or scuttle “a square bucket wide enough for your roller size” can be kept conveniently on the floor at all times.