It's simple, really. With Start2Invest you first of all decide on the size of your savings buffer. Each month you then save a certain amount towards it. This could be as little as 25 euros a month. And once your savings buffer has been reached, the monthly amount is then automatically invested in an investment plan or investment-type insurance.
If you suddenly need your money, don't worry. Just use what you need and the money you start saving again later is first of all used to bring your saving buffer back up to the mark. You then only start investing again after your buffer amount has been reached.