Anyone who earns, and truly wants to invest in bitcoin won't make excuses. There are strategies in Bitcoin investment that make it easy for anyone to invest, no matter how little they can afford. Its all about determination and taking steps towards your financial goals.
If your earnings is not enough, atleast there are things we buy or expenses we make most times that are unnecessary, its important to start budgeting your expenses look at areas where you buy things which are not essential and save, even if its little by little at a time it will add up over time. You can also consider engaging in other side hustles to increase your income. This way, you can start investing little by little.
I think that instead of reducing your expenses for investing in Bitcoin, you should focus on increasing your income. To start investing, you need to make sure that you have a prudent source of income. Are you able to meet your daily needs with your income
While you are thinking about how to increase your income, it is also better to reduce how you spend your money on the things that don't really give meaning to your life so that you can use the money that is meant for those things and be accumulating bitcoin until you are able to increase your income to the extent where you can spend the way you want, and it will not stop you from accumulating bitcoin. What if it took you like 5 years before you were able to achieve a better income? It is better to "make hay while the sun shines" so that you wouldn't regret in the near future that you saw bitcoin when it was low and you couldn't buy it because you were trying to increase your income first.