1.Keep your brushes clean.I use Ivory soap to wash them.
2.Keep your palette clean.
3.One does not need fancy mediums to paint.I use Linseed oil or paint thinner to thin my paints.
4.The paint should be the consistency of mayonnaise.If not, add some linseed oil to the paint.
5.Think Red,Yellow,and Blue.We only have three primary colors.Have a warm version and a cool version of each primary.I use cad red light,cad yellow med,and ult blue for my warm versions and aliz crim, lemon yellow,and pruss blue for my cool versions.
6.When the light is warm the shadow is cool.When the light is cool the shadow is warm.
7.When one thinks of warm think of fire and the colors that relate to that(Reds,Yellows, oranges). When one thinks of cool think of ice and the colors that relate to that(Blues, greens, purples).
8.Use a warm color to start the drawing with. I use Tera Rosa or burnt Sienna with some paint thinner.
9.Think Dark, Middle tone and light. Place darks first,Middle tones second and lights third.
10.There is a dark family and a light family.No value in the dark family should be as light as anything in the light family.No value in the light family should be as dark as anything in the dark family.
11.Instead of making value changes in the darks and lights, try to make color temperature changes.
12.The deepest darks are warm.
13.Read many oil painting books
14.Watch many oil painting videos
15 Go to many oil painting workshops
16.Paint hundreds of pictures
17.If you do everything from 13 to 16 and still cannot paint well then I just don't know what else to tell ya!
18.Painting is a constant struggle. If your not struggling then your doing something wrong."If it were easy it wouldn't be worth doing!"
19.Always squint and compare when painting
20.Indicate where your sharpest edges are and your lightest lights and darkest darks in the beginning.