A Masternode is a server connected with the network that performs certain tasks related with PrivateSend, which is what the anonymity feature is called, and gets paid for it. It is Proof of Service.
To setup a Masternode you need 10.000 BTDX & a server with a static IP.

Google Doc: How to install a masternode: https://docs.google.com/document/d/1L8AbY225aaoWc3XRxRsWNI8ROLI7QNlZ5RmuW3uQBuI/edit#

INSTALL A MASTERNODE

This is a simple Install for Ubuntu 14.04 just open your terminal and copy this 3 lines
https://github.com/LIMXTEC/BTDX-Masternode-Setup-Ubuntu-1404

wget https://raw.githubusercontent.com/LIMXTEC/BTDX-Masternode-Setup-Ubuntu-1404/master/btdxsetup.sh
chmod +x btdxsetup.sh
./btdxsetup.sh
Enter your local masternode genkey

Open Console on local Wallet and type masternode genkey
send exact 10.000 BTDX to a address
edit local bitcloud.conf
rpcuser=RANDOMUSERNAME
rpcpassword=RANDOMPASSWORD
masternode=1
masternodeprivkey=YOUR GENKEY
masternodeaddr=YOUR SERVERIP
server=1
listen=1
after wallet restart also 15 confirms
open console and type 'masternode start'