For repaints always give your walls a light sand before you paint to get the smoothest finish possible. For new drywall always use a drywall sealer first and sand in-between each coat for a smooth finish. Fill any holes and dents with a filler such as Drydex or Sur Patch and sand smooth before painting. An Eggshell finish will be your best finish for durability and sheen, each manufacturer has different amounts of acrylic in their paints (the more acrylic the more durable but also makes the walls more shiny which shows more imperfections) We use Super II Eggshell from Cloverdale Paints which we find has the best balance between durability/washability and not being too shiny. As with picking the best paint the quality of the tools you use will add to the final finish of your painting project. We always use microfibre rollers on Interior paint jobs, they give the best texture to the walls and last a long time if you take care of them.
Do not become over reliant on painters tape for cutting in, tape will almost always bleed thru and people get a false sense of security and tend to get more sloppy. Take your time, use a good sash brush, I like a 2 1/2” brush, and the more effort you put in the better your work will look.
For doors and trim a Semi Gloss finish is the most common paint to use. If i was to give one piece of advise when it comes to painting doors and trim it would be this. The least amount of times you touch the doors and trim with a brush the better!! Dry brush lines stand out like a sore thumb and look terrible and amateurish when you’re done. Use a microfibre wiz roller on the face of all surfaces if possible, work out any brush lines with the roller when possible for the smoothest finish. Take your time but don’t take too long, as soon as you touch the surface with that paint it is starting to dry so you want to work it out as quick as possible. If you have to stop find a good break point like a joint to cut it off so you don’t get overlap lines, this goes for walls as well. When on final coat never stop mid wall and let it dry you will see that lap line when you’re done, always go end to end before you stop for the best finish. And finally, when painting your walls don’t use too much paint on your roller. You will get the feel for what the right amount is and always work the paint out before dipping your roller in more paint, you can always add more paint if you need to but you can’t take it off if you slop on too much. This will give you the best texture and make it look like a pro painted your home. Good luck!