I've had social anxiety most of my life, and over the past few months have only just started to like myself. I can very much empathise with your situation, so I'll just list a few of the things that have helped me into this new frame of mind :)
(1) As you say you have been diagnosed, I am assuming that you are seeing a counsellor or a therapist of some kind? I found it so helpful to have that kind of transparent, private person to talk things through. With a therapist I worked through things like ACT (Acceptance and Commitment Therapy), which worked really well for me. ACT encompasses the things below, which I also worked on in my own time.
(2) Mindfulness/meditation. Being present helps a lot with the social interaction side of things. When I am in a present state (happens more frequently now), I am not scared of talking, or my opinions being taken the wrong way. Perhaps more importantly, when I feel like this, things to say just pop into my head naturally as the conversation flows! It's really helped me connect with people more meaningfully. We can use band-aid solutions (like thinking about topics to talk about beforehand) in social situations, but ultimately they are band-aid solutions. I mention meditation, as I cultivated a daily practice (starting with 10 minutes per day) to get myself used to being present. Over time, this practice began to seep into my everyday life, and I was able to be more present throughout the day- naturally!
(3) Self Compassion/Non-resistance. Accepting myself for who I am. Like Timshel talked about- focussing on the things we can change. For me, I am kind of short and have a big head. Our imperfections make us perfect. I think this is something that can't really be explained over text; however, it involves separating thought from emotion, noticing our emotions and choosing our reactions to them. Sounds kind of whack- I can talk more about it if you'd like; however, I think that a counsellor using ACT could explain it best.
I hope this has helped! Feel free to keep talking if you wish, I try to check my threads daily.
Nice to meet you :)