Starting a Self-Help Journey: Seeking Advice and Suggestions

How does one start a self-help journey? I'm attending weekly therapy which helps, I take my required medication everyday for depression, ADHD, and anxiety attacks which helps as well, but other than that, I still feel extremely depressed, and I do believe it's because I say I'll do better and try to heal and get through life, but then I purposely am mean to myself, I act irritable towards others unintentionally, and just choose to stay negative and choose to feel depressed even when my day is okay. And for the longest time I'd excuse it as "Oh well I can't help it if I feel this depressed" and blah blah blah. However, there are some things we can and can't help with our mental health and mentality and the way I'm feeling and acting is something I feel I can help, but I truly don't know where to start. If you have any advice, suggestions, stories, etc, please comment below, I truly want to help myself heal and learn how to heal and feel happy 😊