A manual for the Helix Junior is available using the link below. While there is technically not an equivalent manual for the standard Helix, the Standard Helix is very similar to the Helix Junior, and the manual below is a great reference for both Helixes. This is a great manual if you are just getting started and want an overview that will give you the basics quickly.
There are manuals available for the SimpleBGC GUI as well. These are very detailed manuals that are great for reference when you want to find out more about something that you see in the GUI. They would likely be a bit overwhelming to try to read/understand when you are first getting started. Select the appropriate manual based on your current firmware/GUI version.