How do I turn on repeats in MuseScore?
Select a measure, then click the desired repeat symbol in the palette (double-click in versions prior to 3.4). Drag and drop a repeat symbol from the palette onto (not above!) the desired measure (so the measure changes color).
How do you make a repeat sign?
The "Right Facing" Repeat Sign is written at the very beginning of the first measure of the section to be repeated. The "Right Facing" Repeat Sign is two dots placed AFTER the Double (Final) Bar Line. The "Left Facing" Repeat Sign is written at the very end of the last measure of the section to be played twice.