How do I draw perfectly straight lines in stage builder?

As the title says -- I'm having issues drawing completely straight lines using my fingers in the stage builder. I'm trying to draw a hexagon, but obviously it's pretty difficult to make any shape that isn't a rectangle or a circle.

Solution 1:

There are three ways to draw straight lines in Stage Builder:

• Hold L or R while drawing
• Enable the grid with - to make lines snap to the grid
• Tap a point on the screen to start a line, then tap where you want the line to end

Source: smashfan63 & testing on my own Switch

Solution 2:

You can press Y (well, the one on the switch) to bring up different layers and from there activate the grid and make it much easier to draw shapes!