Sand the wall patches with 150 grit sandpaper and feather the edges to make the patched areas even with the wall's surface. Sanding the patches will also create a rough surface that will take paint well.
Apply primer to the patched area, using a paintbrush. Primer will prevent the wall filler from absorbing paint and altering its tone. Allow the primer to dry completely.
Pour paint into a paint tray. Use paint that exactly matches the existing paint on the wall. If you don't have matching paint, mix same-brand paints to achieve the desired color or bring a sample of the old paint to a paint store to find a matching paint.
Dab a paint roller into the paint. Choose a roller just big enough to cover the patched area. Cover the roller with a sleeve that matches the texture on the wall.
Roll the paint over the patched areas. Use light strokes and lift up on the edges to erase visible roller strokes.