Just buy them. Yes, really.

Other methods are probably less "secure" or have increased risk (ie. Mining).

Make it a habit to invest a portion of your income to purchase bitcoin, and at the end of the decade you will end with a lot of bitcoin. Just pick a number and stick to that (ie. 20% of your monthly income).

And yeah, ignore bitcoin price, whatever price you buy now, will surely be less than in 10 years or so. Think long term, and as a matter of fact, learn how to make an off line wallet using Electrum by writing some words in a piece of paper with your own hands. Then any funds you send there are untouchable...