You make one other creature you touch -- including its clothing, armor, weapons, and other belongings on its person--look different until the spell ends or until you use your action to dismiss it. The target can seem 1 foot shorter or taller and can appear gaunt, obese, or in between. You can't change its body type, so you must give it a form that has the same basic arrangement of limbs. Otherwise, the extent of the illusion is up to you.

The changes made by this spell fail to hold up to physical inspection. For example, if you use this spell to add a cloak to the target's outfit, objects pass through the cloak, and anyone who touches it would feel nothing or would feel the target's actual clothing or lack thereof. If you use this spell to make the target appear fatter than it is, the hand of someone who reaches out to touch it would not stop when it appeared that it should but would seem to pass through the target's body.

To discern that the target is disguised, a creature can use its action to inspect the target's appearance and must succeed on an Intelligence (Investigation) check against your spell save DC. 

If the target is unwilling when you cast the spell, you make a melee spell attack against it. On a hit, the target must make a Charisma saving throw, becoming disguised only on a failed saving throw.