The biggest challenge of pantomime is clarity.
A good technique for judging how clear your poses are is to look at them in silhouette.
Also, video reference is incredibly useful as a tool for good body mechanics.
-Strive for clarity in your pantomime so that an audience can clearly understand both what the characters are doing and also what they are thinking and feeling.
-Focus on strong, clear poses that are both aesthetically pleasing and tell the story.
-Make sure that the timing in your shot helps the character feel like it is thinking as well as doing.
-Give the eyes plenty of attention in your animation, because they can totally sell your character's internal process.
-Make sure that your acting choices feel real and not contrived. Avoid the cliches when possible. Pantomime can be cartoony or realistic, but the character needs to be believable in either scenario.
-Use video reference as a tool for planning your shot and as a reference for body mechanics.
-Be sure to enjoy yourself. Shots always turn out better when you have fun working on them