99% of the time, you only need to pay attention to the top white row channels and the red row channels immediately below.
The top white rows shows you the keyframes for all the bones in the Bone layer. This is mainly useful for making
global timing adjustments to that bone layer. (For example, to speed up or slow down the character.)
The red rows are for editing the currently selected bone(s). Use this to monitor and edit the bones you're currently animating.
The other color Bone channels can usually be ignored. As a matter of fact, I like to disable them entirely from the timeline. There's more about this in this video (scrub to 8:54):
Better Default Settings for Moho Pro
Other channels in the Bone layer are mainly for transforming the layer. Note: I like to put the Bones layer inside a Group layer and do my layer transforms on the group layer. This isn't necessary but sometimes it's convenient to keep these keyframes separated. (For me, the Group transforms are usually for secondary animation, like adding squash and stretch when the character is running.)
If you need to see channels for multiple layers (bones, artwork or whatever,) all at once, you should use Timeline Visibility in the Layers window--that's the column with the Stopwatch over it. Activating this on a layer makes the layer's active channels persist in the Timeline even when that layer is not selected. This is useful when you have keyframes in multiple layers that need to be edited in sync with each other. (BTW, Stan's
Layer Selection Buttons offers a convenient way to access Timeline Visibility without drilling down the layers.)
In general, I try to minimize what I see in the timeline to only what I'm currently working on. Displaying too many keyframes at once is confusing and can slow down Moho's UI performance.
Hope this helps.