The time to buy is when nobody is talking about it during the months after a major price drop aka Dump. Prepare now and look at it as a long term project - years. To be blunt £50 isn’t what you need to do this properly. Also right now the cost per transaction is at it’s highest ever, trading coins costs you a small % depending on how busy the blockchain is. What I and a lot of others did was inject a lump sum, worked away trading and withdrawing profit until the seed money was back in the UK Bank. Then you’re trading with just your profits, have a strategy and buy/sell/convert to that plan, it’s not a get rich quick method where you buy cheap and sell high cos you got super lucky, but it’s done fine so far.
Basically find a UK Bank willing to link with Coinbase (I use First Direct) or use Revolut. Setup a Coinbase Account (you will need to prove who you are with some form of UK ID for Regulatory and Tax purposes) and transfer some £s. Next go to the Coinbase Pro site and pull your funds in from Coinbase, it’s way cheaper to trade on Pro than the customer centric Coinbase main site. Then buy some Crypto. This is just one way there are umpteen places like Coinbase - Binance is a biggie and other ways to fund them.
If things follow form there will be a big plummet in value soonish then a couple years before it flies up again, each time the low and high go up in what they are in £ terms, the last stablish low was about £5K, this time rather than £10K as I was expecting it might be £20K or £30K, who knows. However with the Finance guys, Amazon, Tesla and a few others like Mastercard making noises it may not follow the old pattern.
Should stress that it's not an investment, it’s a total gamble, but imho so are the rest of the stocks/shares markets at the minute, until COVID is suppressed and the reality of what the USA/EU/UK printing a whole lotta money actually ends up doing to the economy.
If you want more detailed info PM me, happy to help. There is loads of info if you Google and have a look at the various FAQs.