Understanding and Approach:
When teaching a 16-year-old autistic son about masturbation and cleanliness, it's important to use clear, simple language and a step-by-step approach. Be patient and supportive, respecting his learning style and comfort level.

Step 1: Explain What Masturbation Is
Use straightforward and factual language, such as: "Masturbation means touching your own body to feel good and relieve stress. It’s a private activity that happens in private places like your bedroom or bathroom." Avoid slang or euphemisms to reduce confusion.

Step 2: Explain Privacy and Appropriate Settings
Emphasize that masturbation is something to do in private places, not in public or around others. You can say: "It’s important to only do this when you are alone, such as in your bedroom or bathroom, with the door closed."

Step 3: Teach Hygiene Practices
Explain gently that after masturbation there may be fluids or mess, and it’s important to clean up promptly for health and cleanliness. You can explain:
- Use tissues or toilet paper to wipe yourself afterward.
- Dispose of the tissues in the trash bin.
- Wash your hands with soap and water to keep them clean.
Consider using visual supports like pictures or checklists showing these steps.

Step 4: Introduce Step-By-Step Technique for Using Tissues
Break down the process into simple steps:
1. Keep tissues or toilet paper nearby before you start.
2. After finishing, take a few tissues and gently wipe the area where the fluid is.
3. Fold or roll the used tissues carefully so nothing leaks.
4. Throw the used tissues into the trash bin.
5. Wash your hands with soap and water thoroughly.
You can role-play or demonstrate these steps if he is comfortable.

Step 5: Reinforce and Support
Remind him that making a little mess is okay but cleaning up is important. Encourage him when he follows the steps well.

Additional Tips:
- Use clear, consistent language.
- Keep explanations short and repeat as needed.
- Use social stories or visual cues to support understanding.
- Answer questions honestly and calmly.
- Respect his privacy and comfort throughout the process.

By breaking down the concepts into manageable steps and being gentle and patient, you can help your son develop good hygiene habits related to masturbation.