Probably the best way to grow your Bitcoins is to save them and wait for about a year. By then the price will probably have gone up by then and you will have a substantial amount of money.
Putting coins in sleep mode for a year is a slow method and we are not sure what will be the price after a year. Much better to rotate it in your storage so while waiting for your price expectations there's still a moving coins competiting in the investment industry.