Here are some options:
1. For "disgusting" or "unpleasant":
* "Yuck" sign: Make a face of disgust and wave your hand away from your face.
* "Ugh" sign: Make a face of disgust and bring your hand to your forehead, scrunching your nose.
2. For "gross" as in "a lot":
* "Lots" sign: Make a fist with your dominant hand and shake it repeatedly.
* "Many" sign: Hold your open hand facing upwards and move it forward repeatedly.
3. For "gross" as in "disgusting appearance":
* "Ugly" sign: Make a "U" shape with your index finger and thumb and move it back and forth across your face.
Important Note: Signing is nuanced, and the best way to convey the meaning of "gross" in ASL is to use the appropriate sign or combination of signs based on the specific context and what you're trying to communicate.
It's best to learn ASL from a qualified instructor or resource.