Both. To invest you need to have some saved up and it's a bad idea to invest the money you're living on.
If you're really afraid of investing do yourself a favor and don't keep your savings in a bank. Buy a good safe or a piece of land that will work as both a store of value and an investment.
Moreover, if you want safe and sure profit, saving is the best thing you can do, if you are going save bitcoin not the money/cash itself which you are going to save it in the bank. Of course, was the best one to save it then hold it in a long term basis because of the volatility it has.
Yes, I agree the best option is to save your bitcoins that you have bought or collected through your earnings by various means.
It will be the best option as we can see that in a long term the BTC is going to be more establish and will have more power than the current it have. As the prices in the future will go higher and you can enjoy much more of it than you can now a day.
Looking now, the price is really high. The future of it is unpredictable but we hope that it continues to rise even more. A lot of people are correct with storing just bitcoins and wait till the price is so high. I think you could enjoy more, and a lot more.