if you neglect your social life it will naturally atrophy. as
@Amante Silvestre pointed out it's much easier to work on social acuity when you're not outcome focused. be process focused. mastering a hobby or instrument naturally pushes you to be process focused. it builds resilience and consistency(because any growth is built on constant failures), gives you opportunities to socialize/build connections(as long as the hobby is something that can be done as part of a group), and cultivates confidence(due to the newly developed expertise) in a positive feedback loop.
for something more immediate i would advise OLD and acting as the ideal lover. since you're only seeking casual sex you won't build deep or long term relationships with women. that means you can be anyone you want, so remain mysterious and playful. put up a simple profile that says you're only looking for fun and a couple stupid joke lines, this will help naturally filter out girls looking for something more serious. be bold and nefarious on your dates. be sexually aggressive and smooth, they know what they signed up for. the caliber of women you'll get won't be the best(they'll probably be crazy and have their own life in disarray, seeking a sexual outlet and willing to take risks), but they might give you some of the best sex you've ever had. i would say within 10 OLD dates you should get at least one lay, possibly a FWB. ignore your flaws because you will never show them. you'll simply stop talking to the girl if a flaw ever surfaces, you won't give her the chance to uncover these. this means be confident in the facade, you will never show the real you. with these girls you'll also have to indirectly objectify them to escalate and show the figurative balls they want so desperately to suck on. by this i mean use them for what you want in the bedroom. once you kiss her on your date start getting handsy and tongue, bite, and play with her. breathe in her ear, put her hand on your c0ck and be bold. grab everything while making out with her. rub your hand on her cliit over the pants then slip your hand in her pants, get under her shirt and pinch her nips. do all this in some tucked away corner of the venue you're at, there are no rules with these girls. when you get somewhere private USE her. if you're not hard tell her or push her to suck you off until you are. if she's not putting suction on it tell her to. slap her ass, finger her hard, grab her hair and pull her around, command her to your liking. tell her to do what will make you hard then fuuck her brains out. these kinds of women LOVE this stuff. and you'll be surprised by how many women are like this. they all are to different degrees tbh.
but be warned, the above is not a long term solution and has a price. it's a deceitful act meant to personify what a risk taking crazy girl perceives as an ideal man. you must never identify with the facade. always remember that it's not the real you and it's an act, a tool you're using to simply objectify women and bust a nut. it's also a hobby, but not a very healthy one. you'll get good at sex and escalation but not much else. you must NEVER allow yourself to feel validated by the results of this facade.
the problem is to play any part well you HAVE to identify with the character. so to be good at this and for it to be extremely enjoyable you will forget about your flaws and assume they don't exist. you will validate yourself by how much sex you're getting, how enjoyable it is, how much a girl submits to objectification and it will screw you up in the head. you will have the strongest orgasms and the most enjoyable times from a strictly hedonistic perspective but you will undoubtedly develop some kind of disorder. you won't notice any of this because it'll be a massive thrill and you'll be too busy chasing orgasms and ignoring your faults. you will also be encountering girls that are not mentally healthy and doing the same as you. they will also have disorders(though you may not notice until you get some experience) and will be destroying themselves in a similar fashion. they may try to convince you to bust inside them, they may steal things from you, they will surely lie constantly, and they will attempt to manipulate you in subtle ways. they will probably not realize they're doing any of this because they're too busy chasing the high, too far down the rabbit hole. many will be cluster b chicks.
you will either eventually snap out of it and realize this is a waste of your precious time as it demeans you, or you'll fall down the rabbit hole in a swirl of manic rationalization based on frivolous and trivial things. it could easily lead to drug dependency, depression, or otherwise a life you don't want.
if you do try to maintain a detachment from the 'ideal lover' identity you'll either find the activity boring and monotonous or deplorable and disgusting. so you will naturally polarize yourself to do it completely or not at all. that is the danger of this approach.
you're basically too naive and have no idea what you're getting into. you want hot passionate sex without putting in the proper work. you are asking for a means to self destruct. you will naturally learn by being burned, just like i and many other men were.