My best advice so far, take small steps towards your SR.
Usually the first few matches are the roughest, mostly due to if you lose SR your emotions can get best of you immediately, might have unfortunate situations, but stay positive, play your best next match, do everything you possibly can all while making sure your team stays in positive mindset.
Give props to your teammates on successful holds, believe in them, as they can be your teammates next game as well, make friends with them so you can climb the ladder together, even while Solo Que.
Once you surpassed your SR, take a break, relax, make sure you feel 100% ready for next match regardless of win or lose, you know you can play your best.
Sometimes if you win your first 2 games, take a break come back in few hours repeat the process, and If you lose 2, try your best to win next 3 then take a break.
Also if you passed people on your friendlist, tell them gl wish them the best next match, same goes for those on enemy team, sometimes they have issues as well, positivity can go long way, make sure everyone in match is having a good time, cause that’s what its all about, having fun and making friends. Possibly might be paired with them next match, Hope this helps!