Make sure you don't push yourself too hard. I was just reading one of the top AskReddit posts from today and it was all about "what mistakes people make when they start up at the gym?" People usually push themselves super aggressively, see a big change in their weight and muscle mass in the first few weeks, but then crash hard and don't go back, only to repeat the process every few months/years.
Not saying you're doing that and I'm pretty sure you've worked out before (I remember you saying that you did in the past at least) so maybe this tip isn't necessary, but definitely take things really, really slow. It's not about pushing yourself hard and lifting huge amounts of weight, it's mostly about eating right, doing a comfortable amount of weight, properly lifting and controlling the weight, and performing lifts and movements in their entirety.
I'm mostly just good at regurgitating info though, so take what I've said with a grain of salt and confirm it yourself if you need to. All things considered, just take it slow, the results will happen even if you don't think they will.
