Typical workflow

Drag drop a video file into player to load or use ⌘/CTRL+O.
Press SPACE to play/pause or ◀▶, ,. to seek back/forth
Select the cut start and end time. Press I to select the start time, O to select the end time for the cut.
If you want to cut more segments out of the video, press + or the c+ button to add another segment, then select the next segment with I/O.
If you want to re-merge all the selected segments after cutting, toggle the button nm (no merge) to am (auto merge). This is useful for cutting away certain parts of a video (by selecting everything except the parts not needed.)
If you want to export to a certain dir, press the custom output dir button (default: input file dir)
If you want to override orientation metadata, press the rotation button
Press the scissors button (or E) to export the slice
Press the camera button (or C) to take a snapshot
If you want to move the original file to trash, press the trash button
Note: The original video files will not be modified. Instead it creates a lossless export in the same directory as the original file with from/to timestamps. Note that the cut is currently not precise around the cutpoints, so video before/after the nearest keyframe will be lost. EXIF data is preserved.