Image software for creating a repetitive background of seamless tiles

Question

I want to create a background for a website of mine. The image should be able repeat seamlessly so the background can be scaled to any size.

For example, It should look like this site.

I have no knowledge in any image software besides MS paint.

So what software should I use to make something like that more easy? Does maybe gimp has a feature to make an image like this or some other free software?

Example result I want to create:

_{(source: skribbl.io)}

Answer 1

I recommend Paint.NET with the Seamless Helper Plugin (direct download). After installation of Paint.NET, you need to copy that DLL file to C:\Program Files\paint.net\Effects\SeamlessHelper.dll.

Here's how easy it is:

1. Create a new picture with even pixel length. I use 200x200 px here.

2. Draw something on the center horizontal and vertical lines, like so:

3. From the Effects menu, choose Seamless helper. The picture will then look like this:

4. Go on painting.

5. Repeat it on your Website