You scuff up existing paint for two reasons. First, you want to get rid of any oil, grease or dirt trapped in the top layer of paint. This is the stuff that cleaners and degreasers can't get off. The second reason to scuff is to set up a physical bond for the new primer and paint to adhere to. You want to give the old paint some tooth so the new sticks better.
If paints have been allowed to stand and hard lumps or skin have formed, the skin or scum should be removed, after which the paint can be stirred and strained through screen wire or through one or two thicknesses of cheesecloth.
There are two bases of paint for your house: solvent-based (oil or alkyd) and water-based (latex). Oil-based paints dry slow - usually taking up to 24 hours. The best clean up for an oil-based paint is turpentine or paint thinner. Latex paints' advantage is that it dries relatively fast, but it is not desirable in hot weather or direct sunshine. The best clean up for latex paints requires just soap and water. So if you are painting the inside of your house, it is recommended to use water-based paints, while solvent-based paints are suggested for painting the exterior of your house.
If new caulk is applied, main body portion needs to be touched up, and most of the time new paint will not match aged paint even using exactly the same paint out of the same paint can, as sheen difference will come into play.
However, if you put a coat of pure white primer (which has a score of 0) on top of the brown color wall first, this immediately brings your luminosity score down to 4 (8 + 0 = 8/2 = 4, the average). This means you may only need one coat of yellow paint to give you the right hue and saturation. In reality of course, you will always want to do at least 2 coats. But even with a total of 3 coats (primer and paint) you are way ahead of the paint-only option.
If one has a bleaching or highlighting services done to their hair. The hair will be dryer from the use of bleach, or other lightening products with the addition of developer. Again, there are many remedies on the market today to alleviate the drying affect of coloring services given to the hair. Not to worry.
If you are a Summer (Light and Cool), your colors mimic the soft colors of the sky and sea with their cool and soft blue undertones. Summer women receive compliments with pastel shades such as rose, periwinkle and sage. Avoid wearing colors in rust, terra cotta and any shade of orange. Accessories in silver, white gold, opal and pewter accent your look.