You can use GIMP to digitally design and create any number of backgrounds. Employ the Gradient Tool to create subtle colour variations, and take advantage of one of the many marking tools to embellish the foreground. For example, you can use an orange gradient and black markings to create a tiger-skin pattern. You can freehand the pattern, or you can use simple geometric designs coupled with GIMP effects to produce an artistic background in a few steps.
Launch "GIMP" and make a new file by clicking on "File" and "New." Choose a "Template" file size or insert custom dimensions of your choice. Click "OK" when you are finished. A blank workbook appears.
Select the "Blend Tool" located in the main toolbar, and the "Blend" settings appear in the bottom half of the toolbar. Click on the "Gradient" box to open up the menu options. Scroll down to "Yellow Orange" and click on it. Double-click your cursor on the top left side of your workbook, and drag it across the screen to the bottom right side. A yellow-to-orange gradient appears.
Insert a new layer by clicking on "Layer" and "New Layer." Within the "Create a New Layer" pop-up box, select a "Layer Fill Type" of "Transparency." Click "OK" to finalise inserting your new layer.
Click on the "Paintbrush Tool" and make sure the "Foreground Color" box is black. In the "Paintbrush Settings" located in the bottom half of the toolbar, click on the "Brush" icon and select "Calligraphic Brush#1." Increase the "Scale" or size of brush as desired.
Use the paintbrush to draw isosceles triangular shapes, with the base of the triangle on the border and the smallest angle of the triangle pointing toward the centre. You can use the "Eraser Tool" to eliminate any erroneous marking, but these lines need not be perfect as you will apply additional effects as needed.
Select the "Filters" tab, and click on "Distort" and then "Ripple." Select the "Orientation" to be "Horizontal" and the "Edges" to be type "Wrap." Preview both "Wave Types" to see if you prefer "Sawtooth" or "Sine," and increase the "Period" until you are satisfied with the type of curve you can see. Depending on the size of your workbook, you may be satisfied with a period of around 200 and an amplitude of 5. Click "OK" when you are ready to implement the changes.
Save your tiger-skin background when you are finished by clicking on "File" and "Save As." In GIMP, you can choose from multiple file extensions such as ".jpg," ".png" and ".gif."
Draw a few large triangular shapes at a time, if desired, and shrink the layer to produce a cleaner-looking line than you initially produced. To adjust the layer size, click on "Layer" and "Scale Layer." Decrease the width and click "Scale" when content. You can use the "Move Tool" in the main toolbar to double-click and drag your layer where you want it to be. Insert a new layer to continue filling out the tiger-skin pattern elsewhere.
When you save your file using a picture extension that does not support multiple layers, such as ".jpg," you will be prompted during the "Save As" process to "Export File," which will merge your separate layers.