7 Ways To Set Boundaries Without Being Mean

1. Start saying “No” To change your ways, you must always start small and in this scenario pick something minor to say no to. ... 

2. Trust your body instinct. ... 

3. Let go of what people will think. ... 

4. Stay firm. ... 

5. Be short and confident in your “No” ... 

6. Be clear about what “Yes” means. ... 

7. Implement ASAP.

ASSA stands for:

• Alert the individual that you need to talk to them.

• State your issue by revealing to the person what the problem is. Tell them why it’s an issue.

• Sell the advantages to them for acting better towards you. For example, “you will seem professional”.

• Agree. Seek agreement for doing things differently in future.

https://www.lifehack.org/articles/communication/7-ways-set-boundaries-without-being-mean.html