You can't, on purpose.

The idea is that there are two kinds of investors: Sophisticated ones who can look out for themselves, and regular joes, who are protected against being ripped off by extra regulations and extra paperwork. Bitcoin futures aren't the kind of product for which anyone will go though those regulations and do that paperwork.

Now, how do you become a sophisticated investor? First of all, have a spare million or tow. Next, fill out a quite simple form.

Interactive Brokers is providing access to the CBOE futures to retail investors. Appears to be long positions only at the moment with high margin requirements, but it's something.

Many of the other large retail brokerages said they would offer them pending liquidity/volume thresholds.

I can imagine bitcoin will one day become tightly regulated and only available to sophisticated traders; the network only supports 15 transactions per second, limiting who can do trades is one way to deal with it. NYSE can do about 11K a second (based on https://www.quora.com/What-is-the-average-total-number-of-tr...)

The amount of transactions the bitcoin network can handle is totally unrelated to the amount of trades that can be performed on exchanges.

Correct, however, the number of transactions that can be handled does matter when it comes to moving BTC out of or between exchanges.

BitMEX is offering BTC Futures since 2014 for joes like me and you. Only caveat: your profits and losses are all realized in bitcoin.

Looks like TD Ameritrade also has them - I'm getting price data from my app for it at the minimum.

You need to find a futures broker that offers it, and open account with them...