I never read any tutorials on how to use it so I can't recommend any :/

Since I am mostly importing SVG into the program, I don't actually need to deal with creating any layers in Synfig. Here are the basics:

1. Drag the play head to a frame where you want things to change
2. Turn on animation mode (main canvas bottom right)
3. Set the interpolation (next to animation mode button). Ease is often a good one
4. Select a layer to edit (you can select multiple)
5. Drag the nodes around to move them
6. Congrats! You just animated those node from frame 0 to wherever your play head is on!

Do keep in mind about some bugs while important Inkscape SVGs:

• If you copied some objects from 1 Inkscape file to another, your gradients are likely broken
• Clipping doesn't work out of the box. Duplicate the lower layer, group it with the higher layer, set the higher layer's composite method to "Straight Onto"

There are a lot more small problems above those.