What’s an easy way of being comfortable and stop masking my autism?

It depends on what "traits" you want to mask.  Autism is such a wide spectrum that makes this question hard.

I would first want to talk to you about your self-esteem. Work on creating a support system you feel comfortable around, so you don't have to mask any of "YOU!". :)  Our support systems and who we have around us can impact our daily functioning. If we have supportive people who challenge us and call us out when needed, we know we have a solid foundation for support. I would start by asking, "What feedback do you receive from your support system?"  Having honest conversations with those that matter and are in your "bubble" can give valid, fair, and needed feedback on what they see as room for growth.

Within that, sometimes we need to learn and work on dismissing people's opinions outside of our "donut of control."  

Second, you can work on some self-esteem skills to allow you to feel comfortable with being you. We can increase self-esteem by working on how we talk to ourselves.  Self-talk is a powerful tool. We can talk to ourselves or beat ourselves down with our words. We can work on learning tools that assist us in reframing our thoughts and questions so that it does not put us down.

Another great tool is being more aware of our thoughts. Let's look into "stinking thinking." Are there any cognitive distortions you need to identify, verbalize and reframe?  These simple skills can take time, as habits are hard to break. However, as you are working with a therapist, you can key into the skills that best help you feel more comfortable with yourself and grow in skills you want to better yourself in. 

We can always improve ourselves and work on the areas you feel need to be worked on from there. Are you wanting to feel comfortable in social settings, learn how to be in-tune with others.  This can be done by learning coping skills that allow you to handle these situations, such as grounding techniques, learning social skills, etc. 

Again, I know this doesn't necessarily give you an answer to your question, but again, I would want to know more about what you want to mask.