Painting always has the potential to becomes messy if you are not careful and do not prepare the area for the job. You need drop-cloths to protect your floor from paint splattering. These can be purchased as plastic sheets or more heavy duty cloth. It may be wise to invest in the cloth variety because they can be reused in the future. A ladder is also need to reach the top portions of the wall. Don't try and reach; the paint can drip off the brush and result in a sloppy job.
In addition to the drop-cloths and the ladder, you will need other preparation materials such as painter's tape. This is used to protect seams along the wall you're painting, whether it's molding, the ceiling, or an adjacent wall. Edging is the more difficult aspect of painting. An optional tool to purchase is an edging tool which can help you cut the corners of the wall and baselines. If you are skilled at edging, painter's tape may not be needed.
Decide how the paint will be applied. Most jobs require a paint brush for edges and tight spaces; a roller is typically used to apply paint to large areas. Paint brushes are sold in a wide range of widths to suit your needs, from one inch to as wide as six inches. For your roller you need an extension pole and a roller handle. Rollers themselves are sold in naps from fine to heavy duty. Medium naps are customary for most interior surface and saturate just enough to spread the paint evenly. A paint pan is also needed to store the paint for your roller.
A paint scrapper can be used to remove old paint in the preparation phase. Spackle may be necessary in the preparation of surfaces as well. This repairs holes and cracks in the wall. Spackle can be applied with a putty knife. Sandpaper will be necessary to smooth out the surfaces of the spackle and in-between coats. Paint primer is applied after the wall is patched, followed by the paint of your choice.