Creating an effect on a DME is based on two elements; sources & transforms.
Sources are usually selected on an M/E's keyer bus.  For example, select a source on M/E 1 keyer 1 bus.  In the keyer control area, make sure that M/E 1 Key 1 is delegated (you can do this by double-pressing the Key 1 button on the M/E's transition panel).  Now with this delegation button lit, select one of the DME's which are in the upper right portion of the keyer control module.  This will route the M/E 1 key 1 source into that channel of DME, although the source will still be going through M/E 1's keyer 1.
Next, go to the transform panel (the one with either the Z-ring or the joystick).  Delegate the DME & use the 2D/3D controls to make the DME do what you want.
You will need to use the Keyframe Editing panel / level delegation panel to create keyframes.  Delegate the DME level (and maybe the M/E 1 level if you want keyframes on it too) and with the RECALL button lit, press the "." button to recall an empty register in which to start building effects.  Use the transform panel to manipulate the channel of DME & use the INSERT button to create keyframes.  Note that INSERT performs an insert-after, which SHIFT+INSERT performs an insert-before.  Create keyframes as necessary.  When you are done, press the STORE button on the Editing panel (above the RECALL button) & just press ENTER (or enter a different number & press ENTER).
So, keyframes in the DME level control the transforms of the DME, while one or more keyframes on the M/E level perform the source routing as well as the M/E condition (keyers on or off, background transitions, etc.).  You could have alternately learned M/E 1 as a snapshot, which would equate to a single-event effect that would not respond to timeline commands, but if you're just starting out it often makes more sense to just delegate the M/E & DME levels & build keyframes into each level.