Yep, I included that in the answer I posted before- see the tiny arrow pointing downwards at the bottom of each of the frames, the one next to “0 sec” by default (here I have made it as 0.1 sec)? 

Click the arrow and change the speed (I usually have mine at 0.1 seconds as you can see above). If you click on the first frame (1), hold down shift and select the last, if you click the arrow on one of them and select the new speed, it will make all of the frames highlighted that same speed (faster than doing it individually). :)

My way might not being the best way and it’s also a little hard to explain but I’ll try.. 

I have the video (Youtube or whatever) up on the screen and play it, pause it, play it, pause it a heap of times and print screen it each time. Each time I print screen it I paste it into Photoshop (hopefully you have Photoshop!). So I’ll end up with lots of layers. Click Window > Animation so that Animation has a tick next to it. This will bring up a little “bar” across the bottom of the screen.

All of the layers on the right-hand side of the window will have a little icon of an eye next to it:

De-select the “eye” from all of the layers except for Layer 1. In the bar thingo at the bottom of the screen, click the little square icon at the bottom here:

After you’ve clicked it, click the box on Layer 2 to make an eye appear. (Is this even making sense???). Then click that same square again. And repeat, i.e.click to make the eye come up on Layer 3 and click the box again. Keep doing that until you’ve done all of the layers. By clicking the little arrow at the bottom of each frame on the bottom bar, you can change the amount of time that that frame appears (I usually change it from 0 sec to 0.1sec), and you can highlight from the first to the last frame to make this quicker.

Crop it as needed. Then click File > Save for Web & Devices. Your screen will look something like this-

Near the bottom right of that window you can change the Percent to make it smaller. Tumblr has a limit as to how big the GIFs may be, I think it’s 500kb?? And then save it and you’re done!

I hope that helped you! Too bad if you don’t have Photoshop though, I don’t know which other programs you can use. Let me know if you have any questions :3