Pay yourself first.
In the book The Wealthy Barber by Canadian David Chilton he offers some very sage advice. The book is told as a story of a barber who cuts hair, talks to his customers, is not an extravagant man but is in reality very wealthy. When asked how he did it he answered:
Pay yourself first. By this he meant take 10% of your income and put it in savings. Then with the remaining 90% of your income, live your life. Only buy the house you can afford with 90%, the car, the vacation, etc.
Never touch that 10%, that is to pay yourself with later (retirement).
I have been following this advice since the late 80's when the book first came out and it is the one rule I have never broken nor will I. 10% of everything I earn, whether it be fiat, crypto or any other form of monetary gain, 10% is always put away.
For anyone in their 20s looking to invest for their future I highly recommend this book and his followup books. They can change your life.