- anti-inflammatories and ice can help with the actual inflammation.
- stay hydrated. kind of goes without saying, but step it up as your body's hoarding a lot of that water in your muscles, so you need more just to keep the overall level good.
- geeeentle stretching feels really good and gives at least temporary relief, and it's also just a good thing to do for keeping the muscle quality long and smooth as it heals.
-foam rolling or other massage don't help in absolute terms afaik but it sure feels like it does while you're doing it. just don't overdo it to the point where you're bruising your muscles on top of what's already troubling them.
- i think i heard vitamin d is one of the few things that may actually help. and i think when i tried it it did seem like it did. just, y'know. don't go overboard and poison yourself with too much of it.

a big hit of protein right after the exercise also helps. too late this time, i guess, but it can't hurt while you're recovering. and i take bcaa's and creatine too, these days. the bcaa's seem like they prevent doms and/or speed recovery. the creatine really makes sure my muscles are properly hydrated so they don't get 'sticky', which may not be technically meaningful for doms but it sure makes me more comfortable.

I would consider starting with lower volume and build up to 5x5 over a period of about 2 weeks.

One example might be 3x3 for the first week then 4x4, 5x5 or something to that effect.

Make sure that your total volume ramps up over a couple weeks and also make sure no individual sets are taken anywhere near failure and you'll likely improve work capacity and also see soreness drop substantially over that period.

pre-lift warmup helps sometimes. like, stretch gently to make sure your muscles are mobile and flexy before you start asking them to move and flex. or if nothing else to get a health check on how sore they are. if you're sore when you start then i'm also a big fan of doing as many warmup sets with the bar as you need before you start to add weight again. just because the app says x sets for warmup doesn't mean you can't/shouldn't tweak that as needed.

post-lift stretching is mandatory, according to my chiropractor anyway. according to him you need to stretch to 'remind' your body which direction to align fibres in while you're body's busy repairing them.

also, just sympathy: first time i squatted it was just air squatting (fairly fast though) in some circuit-training session. i think it took me two or three weeks to recover fully.

I'm just getting back to it after a 6 month hiatus and my experience was that the first workout left me sore for about 5 days. Then, once I finally got brave enough to do the next one, I was sore for about 2 days. After workout 3, I was no longer sore. YMMV.

But, oh, that first workout...!