The images are in Spanish but i think you can understand them.
Please like the post if you think the tutorial has been useful.
The final result is:
[ STEP 1 ] Take the caps of the video and upload them in Photoshop. Then change the size of the gif. Mine is gonna be 500x250px. Note: My gif is big, but i can put many frames because later there’s a step where the gif losesa lot of weight. My gif is gonna have 20 frames (usually a gif of 500px has to have 10 frames or less).
[ STEP 2 ] Sharpen the gif. I sharpen all the layers at once [tutorial] and use Smart Sharpen [settings]. Then add a psd.
[ STEP 3 ] Create a new layer by clicking in this icon at the bottom of the Layers Window. Right click in this icon and choose this option. When you write your text it should look like this and then like this.
[ STEP 4 ] Now click on this icon , right click on the gif and Select Inverse.
[ STEP 5 ] Click on this icon , make sure you’ve chosen the color white and paint the gif (with the first layer selected). It should look like this now. Note: it doesn’t have to be white, you can choose another color.
[ STEP 6 ] Click on this icon again , right click on the gif and click “Deselect”. Your gif is finished! Now File > Save for Web and Devices. Note: when you save it, make sure you choose Forever in the Looping Options.