Finding a view is the same routine every time: choose your direction, flatten the solid onto an imaginary wall behind it, and trace the outline. Three steps, no formula.
The Three Moves
One — pick the direction. Front, side or top. Decide where you're standing.
Two — squash it flat. Imagine pressing the whole solid onto a flat wall in that direction. Anything behind another part just hides behind it — depth disappears.
Three — draw the outline you'd see. That flat shape is the view. Width and height of that shape come straight from the solid.
A Worked One
Take a cuboid that's 3 wide, 2 deep and 2 tall. Front view: stand in front and squash — you see a 3-wide, 2-tall rectangle (depth vanishes). Side view: step round — now you see a 2-wide (that's the depth), 2-tall rectangle. Top view: climb up and look down — you see the footprint, a 3-wide, 2-deep rectangle. Three rectangles, all different sizes, all from one box.
Spotting the Trap Before Rung 3
In the toy, the wrong tiles are usually the solid's other views — the side view offered when you were asked for the front, say. That's deliberate: the most common mistake is grabbing a view that's correct for the solid but for the wrong direction. Always check which direction the question asked for.