Starting a New League (and New Drafts in this League)
In order to start a new league in draft dominator, move your cursor over to the Switch Drafts button at the right of the dark blue bar and then select +New Draft. See the graphic below:
You will then select the league in which you wish to mock draft from the list of imported leagues.
See the graphic below:
There are two levels to tracking your various practice drafts - you name each individual mock draft that you will perform under this league name. If you are practicing for different draft spots, you could name the various drafts as "Drafting from 1.05" or "Drafting from 1.07" to keep track of which mock draft results occur from those starting spots in this particular league. When the league is selected and the draft is named, click the green Create Draft button at bottom right.
The Draft Dominator can take you through multiple mock drafts for each league you are preparing for - so you can see what happens if you take Le'Veon Bell at draft slot 1.04 vs. Antonio Brown at 1.04 (and so forth). As long as you have saved the league settings once, you won't have to go through the setup process for each mock or live draft - in future, you'll just click the Drafts button -> + New Draft -> click league name -> and then type in a draft name. So using the Le'Veon Bell example the draft name might be "Drafting from 1.04; Le'Veon Bell" or "Drafting from 1.04; RB".