This is a great opportunity to learn some helpful communications tools. Google it. I like Chris Voss, he is an international hostage negotiator who teaches how to diffuse confrontations. I took his class on Masterclass.
I was reading a post this morning about someone having a hard time with their parents. I try embracing the things I like about myself and remind myself that my parents love me even when they are trying to "guide me". First thing is to let go of who you think they should be. Your mom is a person trying to make her way through life, trying to do her best. Your dad is a man trying to do his best. You need to manage your expectations of who YOU think they SHOULD be.
If your roles were reversed what do you think you would do? How would you parent you?
When a problem arises, I try speaking slowly and in a calm soothing voice. Sit down. I like the long pause too. I will do a reframing of what they just said, cut out the unnecessary information. "So, let me see if I understand what you are saying." Condense all extra side issues and avoid all emotional content. Example...."You want me to stop watching TV. " long pause let them vent. Ask easy questions. "What do you think is an appropriate amount of time to watch TV?" You don't inject yourself into the question. Keep it general and when they answer, no sarcasm, or theatrics ...... ask instead of fighting back, don't let your emotions get involved. Be calm and use a soft voice, it should bring them out of shouting.......they will strain to hear you and in turn speak at a lower level. Possibly get them to sit, you are two adults having a conversation.
I am 55 my mom is 81 and she has picked on me about my clothes my whole life. I embrace my unique style, oh and stand up straight, get your hair out of your face. She always wants to redecorate my house. I have limited her visits. I have a long history of people telling me, "You're doing it wrong." in one way or another. Oh, and "IF you were thinner, or dressed like everybody else, or acted normal... if, if, if...
My grandmother picked on my mom her whole life. I remember my mom wrote grandmother a nice letter. Grandmother corrected it and sent it back. One of the worst things anyone can say is you're just like grandmother. My Mom gets very offended. I suggest asking your mom about her relationship with her mom. I bet there's where her damage came from. If it's true ask her about being criticized by her mom for her clothes or hair, the same stuff she pulls on you. Hopefully this will remind her how it felt. Ask your dad about his parents, what was it like growing up for him.
Parents 
Any tips for my parents? 
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