This may sound superficial. But I think something you can do in the shortest term that will have the greatest effect is to make yourself presentable every day. This makes you feel decent about yourself and reduces the barriers you feel to going outdoors and interacting with others. Personally, if I have gotten properly dressed, that is all I require of myself in a day. Anything extra I do, I consider gravy.

Practically speaking ... Make sure you have a few clean, decent clothes. Wash your face and hands and brush your teeth twice every day. Shower, shave or trim your beard, and wash your hair at least every other day. Brush your hair and arrange it neatly. If you keep your hair short, get it trimmed at least every six weeks. If it's long, tie it neatly back in a ponytail.

More detail about having a few clean, decent clothes ... You need to do laundry once a week and have enough clean clothes to wear between laundry days. This means, eight pairs each of underwear and socks and eight T-shirts. You wear these all fresh every day. Plus three pairs of pants. You wear a fresh pair of pants every two or three days. Plus a comfortable pair of shoes. And if you live in a cold climate, a sweater and a coat. This doesn't have to be complicated. You can choose classics and multiples of the same item. All solid black T-shirts, bluejeans, black socks, and black sneakers would be fine.

Hope this helps a bit!