For me, Best ever invest money using bitcoins, Just hold them for future. May will taken a few years.
There's no yet risky to do, just waiting and taste your coffee.
Holding alone is already an act of taking risk so make sure you have a back up funds to manage your daily expenses because the moment you invest for long term you must follow your plan to make it effective. When you don't meet the criteria, you might be tempted to spend the money, you must be discipline also, it applies in both investing and gambling.