The expert investors set out to try to beat the S&P, they’re looking for 10% year-on-year, on average. If you want more, you can try the smaller caps, but even there 20-40% is about what you could hope for, if you were lucky. If you want to double it, you need to be basically betting on random unheard of stocks and hoping they suddenly rise in value. Your chance of that happening is approximately zero. Something like 97% of companies are bad investments in the long run, and if you diversify you have a chance that your one good bet will make up for the losses in the others.
Pretty much the entire investment community is expecting a market crash very soon, so there’s almost no chance of anything making 100% return. It’s a pretty sure bet you won’t be making more than 10% either. The best thing to do, rather than wondering what stock will double your return, is to do some research and recalibrate your expectations first.
Whatever you do, make sure that if a crash does happen and it wipes out half or more of your investment, firstly that you can afford that loss, and secondly that you have spare money to buy in the dip to take advantage of the cheaper prices. After a crash, the market will eventually recover (probably) but that could take a couple of years, and if you realise you do need the money after all and sell at a loss, you will regret it.