So I had been skipping on weightlifting the last two months and have been doing nothing but cardio. I decided to start again and hit the weights. I'm on day 3 and I can't fully extend my arms and barely able to take off my shirt. Anybody have any stretching tips or techniques to help with soreness

Dry sauna. Crank up the heat. If not available, scalding hot epson salt bath, completely submerged.

Then there are nonsteroidal anti-inflammatory drugs as well.

Foam rolling and a lacrosse ball work for me.

Or just suck it up, buttercup.

Get a 1.5 in PVC pipe cut at 12 in. Have someone else use that as a foam roller on your arms like they are kneading dough. Also get some kind of oil to help with friction on your skin.

Voltaren.

I was only on it for a week 2 months ago

Serious answer: go shoot baskets for about 10-15 minutes after you're done lifting. Your shot will be way off since your muscles are fatigued but it's great for cooling down and loosening up.

DOMS sucks. its a motivation to keep going to the gym even if its minimal just to avoid dealing with DOMS while starting up again.

Finally went away yesterday , my own fault for skipping on gym

The older you get, or the heavier the weights, the more you need to ice after a workout. You should be able to find some ice cups on Amazon. Freeze water in there and massage when you get done with your w/o.