Required Programs: GIMP
Steps:
1. Open GIMP and go to File>New and select your size (I like 400x150 for banners and 100x100 for Avatars).
2. Brush around
3. Go to File>Open as Layers
4. Select your render and hit Open.
5. Move the render to your desired place. Resize using the scale tool if you need to.
6. Go to the text tool, select your font. Now type your text. Move if you need to.
7. Go to Layer>Transperancy>Alpha to Selection
8. Select two colors
9. Click the Blend tool and draw the line vertically down the text.
10. Now save as .xcf
11. Save as .PNG for best quality during uploading.
12. Upload to image hosting site.
It should come out like this.