This is a simple step-by-step guide on how to install Scala development environment on Ubuntu.

1.  Install Java SDK. Here is a simple guide on how to install Java using apt-get.
2. Install SBT. Either manually download sbt from here and unpack it or use this instruction to get it with apt-get:
   echo "deb https://dl.bintray.com/sbt/debian /" | sudo tee -a /etc/apt/sources.list.d/sbt.list
sudo apt-key adv --keyserver hkp://keyserver.ubuntu.com:80 --recv 642AC823
sudo apt-get update
sudo apt-get install sbt
3. If you plan to use Eclipse for Scala development you can download preconfigured version from here.