learning sign language with mobility issues/chronic joint pain

Hi! I have hEDS and chronic joint pain (and increasingly joint stiffness, yay!) and am currently learning sign language (multiple at once). I really enjoy my classes, but I am noticing that certain signs are just very difficult for me to physically make (basically signs in which the fingers are in different positions - thumb, index and pinky are fine, but if I need to straighten my middle or ring finger while the others are bent it sometimes takes me several attempts to get my fingers in the right position). I was wondering, is there anyone else here with limited hand dexterity that speaks or is learning sign language, and how do you handle this? The finger position can make quite a difference, so I can't just *not* bend my fingers, but I also can't really always successfuly bend them lol, so any advice or experiences would be welcome! (I also struggle with certain positions - for example the sign for grandmother in one of them involves touching your shoulders and then wiggling your shoulders and. yeah. that one isn't going very well or painfree either lol)