gif tips1) Limit the Amount of Frames
Sometimes you don't need 100+ frames, but a lot of people do go over 100. Keep it at a 200 frame maximum. For tumblr users, gifs in sets have to be under 2mb to work so if it exceeds the limit, go in and delete frames. If you use kmplayer: you might want to delete every other frame if you need to. Depending on your settings, you might have a of frames that are very similar and just use up the file space you need.
2) Have a Good Video Downloader/Converter
Make sure you don't have a converter that adds a watermark. I have three different ways to download the videos I want. For youtube videos I use 4kDownload and keepvid. They both have their pros and cons, but I like 4k Download the best, but if you don't want to download a program on your computer then keepvid is your best option. For movies/tv shows that aren't on youtube I usually torrent them. Some people don't like to torrent because it can put your computer at risk, but if you are going to torrent, read the comments for the torrent because someone in the comments will warn you. If you aren't using kmplayer to get your frames, make sure you have a site that downloads your videos in MP4, MOV, AVI, MPG, or MPEG format because those are the formats that I know photoshop accepts..
3) HD Videos = HD Gifs
There is no way to magically get good gifs if your video quality is bad. If you have a 360p or 480p video it is possible to make it look a little better when color and sharpening, but it's not going to look like a gif made from an 1080p video. I usually use 1080p videos and 720p if 1080 isn't available. Sometimes I will gif from a 360p or 480p video if I really want to make the gif.
4) Keep Up With the Trends (Mostly Applies to Gifsets)
A lot of gif trends have been happening for the last couple of years. You don't have to partake in the trend, but I always like knowing about them. Trends can change really fast, for example, gifs that were centered around color were very popular. There was "color porn", pastel gifs, sets that would focus on two colors, and just very color oriented gif sets were very popular. Around March of last year gifs that a bit darker and have lower contrast became really popular, and it's still popular now. The coloring in the gifs are dull and the contrast is low (somewhere between -50 and -100 depending on the frames.)
I like the trend of the dark gifs more because it's not as hard and time consuming as changing colors to make a gif vibrant. The low contrast and and dark adjustment layers does make the gif looks like it's moves smoother and make it looks less grainy.
The first gif has about -50 contrast and the second one is about -75 contrast.
5) Pay Attention to the Timing
If you make your gif from screencaps made with keepvid, you will have a lot more frames. You are going to pick an option under 0.09 seconds. Now if you make a gif that is 0.04 seconds per frame, it will jump down to 0.03 when you upload it online. And, if your gif is 0.05 seconds per frames it will jump to 0.07 seconds. Test out your gifs before you publish them. You can preview your tumblr post before posting and view your gifs to see if any of them or too slow, too fast, or just not working.
6) Read Tutorials
Even if you are confident in your gif skills, sometimes reading tutorials are helpful. It's a good way to test out different settings in photoshop or kmplayer.