In personal's view, Invest on mining as only mining provides the massive amount of profit rate. You may invest half on CEX.IO to help you for a while. (Currently the selling price is normally twice than the searching price.)
The second stage will be on alternative coins.
The third stage will be on money makes money basis.
best method to actually lose money. really bad call in my opinion.
I use a fix amount on a monthly basis to buy bitcoin, as long as it's under 100€ / $150. After it hit the line, I'll buy for half.
see:
invest half of what you really want to invest
and plan to buy more if price drops well below where you first got in.
that way, if price goes up, at least you got to put some money in,
and if price goes down, you get to buy more than you would have gotten.
good luck.