Move the points around so that none of the lines cross.
On a touch screen, a tap does what a click does.
Click on a point and drag it to move it.
On the keyboard, the arrow keys pick out the nearest point in that direction, and Space or Tab steps through the points in turn (Shift+Tab backwards). Enter picks up the chosen point; the arrow keys then move it, and Enter again puts it down.
Hint shows a point to move and where to put it, rather than simply moving it. Nothing in Untangle is forced by logic, so the hint looks for the move that takes the most crossings off the board, and says how many crossings the point’s lines are in before and after.
When no single move takes a crossing away, the hint says so and moves a point toward an untangled layout anyway, telling you what that does to the point’s crossings — which may go up for now — and, when it does, that it frees a move removing some.
The hint picks only spots where its counts hold however your drop lands on the marked spot, and with Snap points to a grid on, only grid points.
These parameters are available from the ‘Custom type…’ option on the ‘Type’ menu.