Brushes and tools Buy good quality brushes for acrylic paint, sable is a good choice. A good set of miniature files and emery paper. Old toothbrush for cleaning Before starting to paint use some method of holding the figure without actually touching it. I use what electricians call a small crocodile clip fixed to a cocktail stick and clamp this to the peg on the foot of the figure. (No peg then drill a small hole in one foot and super glue a paper clip to it).
Preparation If the figure has separate parts such as arms and legs then clean the areas to be fixed and glue together using "Super glue". Leave for 24 hours, then clean off any mould lines with a small file and give the figure a good clean using an old toothbrush in warm water with a few drops of washing up liquid added and rinse in cold water. Leave figure to dry.
Painting There's a lot of painting straight lines and edges when painting drivers, especially the modern ones with all their badges. Always paint with your hands locked together in some way. That way you may still shake, but the brush and the figure will shake at the same speed. You can use different types of paint such as oil, enamel or acrylic. I only use acrylic because it is quick drying and water based. Clean brushes in water (often!). Give the figure a white undercoat (brush or sprayed on) and leave a couple of minutes to dry. Start from the inside out, paint the flesh areas first then shirts and top clothes last. When painting belts and straps it is usually easier to paint the belt first overlapping on both sides then paint either side. Do not try to paint to much detail. An overall flesh colour for the face is better than trying to paint eyes etc, especially in 1/43rd scale. Clothing is not glossy so I give a final coat/s of matt varnish giving shoes a coat of satin varnish to give them a polished look. The only time I use Gloss varnish is for racing drivers helmets.
The above is how I paint and is a personal choice and for guidance only.