Hi mate. I hope its as prosperous for you as it has been for me so far. Buying into BTC totally depends on where you are in the world. Eg, most of the US users use coinbase. I'm from the UK and use the Lykke app (highly recommended). Just remember to look around at the spreads (how much you are buying for vs how much you are selling for). Coinbase and Lykke both have very good rates I find. Coincorner and quickbitcoin were what I was initially using and these spreads were MUCH higher (£100+).
Again, this is something Monaco aim to address making it easy for newcomers to the crypto world.
Finally, if you're new then I highly recommend getting Slack and joining a few slack channels of coins you're interested in. I have found it invaluable for advice. I'm very bullish on MCO too as you can tell by the article, I still think it has strong gains ahead.