WindowPainting.org its representatives and contributing authors will not be held responsible for any liability of any kind for the use of any instruction on any topic related to painting from its site including but not limited to any cleaning or labor involved, replacement of any products or items damaged by their usage. You are notified to use your own judgment and to read manufacturers labels before using any product.

This article is a resource for painting with the sponges you create and is not designed as a guide for painting with sponges that have been preformed.

Most of the sponge materials you will use to create your own sponge designs will hold or absorb a lot of paint. They will be more porous than those you purchase pre-made.
If you're working with regular house paints you will find that your paints will go further than if you're working with tempera or craft acrylics and it will be less necessary to reload your sponge as often. If your painting is meant to be permanent you needn't invest in the more expensive craft paints except when necessary. You may use leftover indoor or outdoor wall paints and shade or mix them with the smaller sized craft paints so long as they are water based. (I it is possible to mix oil and water based colors highlighting with one or the other. However unless you have lacquer thinner you will have destroyed the possibility of cleaning your brushes or sponges for future use. Lacquer thinner may or may not damage certain types of sponges. You may not however use lacquer paint over water or oil based paints as it may lift them, ditto lacquer sealants.)
If it is especially hot or dry while you are painting and will be longer than a few minutes, place your sponges in plastic bags between uses and shade them. You can use a spray bottle of water to keep them from drying out if necessary, and remember that you can always thin your paint. Do be careful not to let paints dry out on your sponges or they will probably be ruined unless you're working with tempera which will wash out even after it's thoroughly dried.
If you are making more than a few sponge prints you will want to find a container large enough to lay your sponge into face down to coat it with paint. When you lift it out simply wipe off any excess paint from around the edges or wherever it appears too thick. Whether you wish to have several colors in your paint basin or a single color, you may proceed by accenting your sponge with additional colors by brushing them directly onto your sponge.
This is a pretty efficient technique, allowing for you to apply the majority of your paint quickly and highlight well. As you will want your highlights to change continually, brush new colors onto your sponges after one or two presses. Even minor differences in color will relieve your design of any manufactured effect, and there will be no comparison to a stencil.
Your paint container can be anything able to hold paint that you can dip your sponge into. Lay down enough paint to cover the bottom so that you can press or rub your sponge into it. If you will be working with a lot of a base color you can go ahead and put in quite an amount of paint, or add as you go along more or less of a color or two to alter it slightly in shade. Styrofoam trays you receive from the supermarket when purchasing certain fruits work well for holding your paint for this purpose. You can use paper plates of course and so on, and if using tempera paints you will be able to use cookie sheets or whatever (cover them with plastic for quick clean up or use a paint roller tray. If you are without a large enough container to lay your sponge in, a flexible sponge can be bent and dipped by segments or you can lay on the paint directly with a foam brush etc.
It makes little difference whether you are painting on a window or a hallway as the process remains virtually unchanged. The difference in painting different surfaces will lie in your selection of paints. Use porch paint for stamping bricks along your walkway and so forth.
'Do not worry if you have built your castles in the air. They are where they should be. Now put the foundations under them.' Henry David Thoreau