A lot of people are trying to purchase Banano right now because it passes every litmus test for a cryptocurrency. It's got a great team of developers, including many from Nano. It has a actual adoption as currency. It's instant and feeless and the power requirements are extremely low.
Here is how to purchase banano before it reaches major exchanges after which the price may explode.
Step 1 : Join their discord. Invitation link is at the bottom of their homepage.
Step 2 : Send ?help as DM to 
You can see all the available commands.
Step 3 : Send ?register
You will get a Nano deposit address
Step 4 : Send some Nano to the deposit address. This Nano will be used to trade Banano
Step 5 : Go to the channel #jungle-bazaar
Step 6 : There will be users there willing to buy and sell Banano.
Step 7 : Find a good sell offer. Let's assume that a user with name bananomoon is willing to sell 27k bananos for 10 Nano and you want to buy that offer.
Step 8 : Now within the channel #jungle-bazaar, make a post like this
?trade 
Step 9 : The moment you post this, you will receive a DM from
"You have created a trade with bananomoon. You SEND 10 NANO in exchange for 27000
BANANO. Use ?confirm to confirm this action or ?canceltrade to cancel"
Step 10 : As is obvious from this message, you have to type ?confirm within the DM with
Step 11: That's it from your part. The seller will confirm the trade and you will recieve your bananos in
your wallet which you can send/receive/trade using another bot called @BananoBot++ within
the banano discord.
Step 12 : To manage your bananos, send a message .help to @Bananobot++ as a DM. You will see all the options including withdrawal/deposit/tipping of bananos
Where to store Bananon coins ?
At present, the online wallet called Banano vault is the best option to store bananos. The link to this wallet can be found in the 'wallets' section of the banano homepage