Before buying bitcoins you should always check bitcoins rate, how bitcoin grew up lately or fell down. And you always need checking all news related with bitcoins, you can still also consulting with person who understands in this theme, just advise you to have in mind major players opinion too.
But among all aspects the main thing you need to consider is the amount of money you are trying to invest in Bitcoin, because I should only invest that much amount of money which he can bear to lose or an amount which can be invested over a long period of time. As short-investment in Bitcoin can be risky due to ups and down but long term investment is surely beneficial.
Investing bitcoin either short term or long term is both beneficial. Close monitoring toward bitcoin price will give enough information and you are always aware of what is the flow in the market. Anyway, it is a good idea of not putting a big amount of money to bitcoin investment if you're doubted on this. Even though investing in bitcoin is risky but it have a big assurance of gaining rather that losing your money.