Simple, i usually use the profit to re-invest it in other crypto.
If you look at the crypto market now, the downtrend of coins has started, bitcoin price now around $34k.
This is a good opportunity to buy and accumulate some top coins in the market, and hold them until we get a decent profit.
Re-investing profit in other coins is good decision, it is very good when their is different investment in cryptocurrency and it can be also risky to have just one investment because anything can happen in the market. In the case where their is no much fund to get other coins, when profits Comes from the first investment it can be used to get other coins.
To re-invest in different cryptocurrencies is always a disponible option, but keep in mind bitcoin is the one which drives this market in all directions while being the safest and most reputable crypto among all. Due to this fact, bitcoin is the best alternative to keep re-investing the profit made, or at least the largest part of it.
Moreover I believe at the beginning of the crypto journey, it's advisable to put hobbies and luxuries aside in order to maximize the re-investments' potential by using 100% or nearly 100% of the profit made to purchase more coins or to keep the portfolio intact generating passive income and growing.
The more the investor does this, the more confortable and abundant it will be his income later. I believe the sacrifices made on the present moment worth on the future when we see the fruits generated through them.