I know alot of ppl need it spelled out for them, so heres some things to get you started on what Janet can do. I found these without looking at any info outside of this thread:
Nut Punch: Safe, mid, restand (+34). Its also reversal/wake-up with invincibility. It still retains its safety (-6) but loses its plus frames (down to +14) when acting as a reversal.
Hop Punch: Admittedly nothing too special. It's very similar to Sonyas "Square Wave" with the difference being, it specializes in a different area. The 2 additional hits—which cost no additonal resources—are not effected by combo gravity and allow for a prolonged periods of air time.
Example: You can do a full juggle with Nitara, end in 2 or 3 Hop Punches which gives her time to buff and end with 5% healing bite.
Tip: The Hop Punches need to have the direction held in order for the additional punches to come out. This can be a pain for overlapping inputs but you can use it to your advantage.
Mime Wall speaks for itself. 3 hits or 9% tank. After 1 of those limits are exceeded she buttsplats.
Janet will butt splat if the main chracter is hit during the stance, much like Sentos kneel. Hitting Janet ends the stance, drains meter, and deactivates her.
Stunt Double start up is about 15 frames slower than Nitara blood buff.
Heres some Stunt Double sequences for beginners. Note: You can buffer 3 attacks into Janet before her meter even turns green. Basic attacks take half as much kameo meter. Movement cannot not be buffered.
Turret: F1, F1, F1
Aggressive shadow kicks: F3, F3, F3
Mix these up in timing & number of instances.
Remember to protect Janet and utilize her taunt.