scrot - is quiet a good screenshotting utility. Below i'll show you how to easily make GIF file with this utility.
First of all, let's start it with a small timing interval:
# cd `mktemp -d`
# while sleep 0.1; do scrot; done
Screenshots will be saved into temporary directory. Perform your actions that you want to record...
Now screenshots are ready. Kill while loop. Move to temp directory. We are going to crop every image:
# for i in *.png; do convert "$i" -crop "+0+10" +repage "$i"
# for i in *.png; do convert "$i" -crop "-10-20" +repage "$i"
In above code: +0 - is left padding, +10 - is top padding, -10 - is right padding, -20 - is bottom padding. Of course, two executions can be merged. Let's resize all of our images and make GIF.
# for i in *.png; do convert "$i" -resize "600x" "$i"; done
# convert -loop 0 -delay 100 *.png animation.gif
GIF is ready. Keep in mind, that GIF format is not suitable for recording long videos.