You hold the "z" button and and click somewhere. A square will appear (a close-up). You press the [ and ] button to enlarge and reduce the size of the circle. You can also hold the Ctrl button and can make a rectangle. You can make a straight line by holding the Shift button and doing the same.

Ok buddy, what you do is press and hold z. Then u can either hold z and move the mouse with your other hand or press z then click the left mouse button to lock the zoom in place. That why its called z because it stands for zoom. If u still dont understand, too bad. Thats as easy as it gets unless your keyboard or mouse is broken. lol :)

Want detailed and small? Check out my Mini Guns saves. I sit there and painstakingly make them pixel by pixel, with no deco, only the color of the elements. Furthermore, they survive upon unpausing!

Also the Z button is very helpful. This is what helped me make my guns so tiny.

The Z button helped me alot. 

The text that comes up when you start TPT has lots of useful stuff in it. You should look at it.

Z button. The final word in TPT when it comes to detail. I called it everyone.

@RAYZR (View Post)

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@Whutchsion (View Post)

 Also pressing "`" button(under escape) will bring down the console where you can type in commands to alter the settings of elements. read https://powdertoy.co.uk/Wiki/W/Using_the_console.html for a complete guide on using the console. You can press tab to cycle the cursor shape between circle, square and triangle. the standard cut,copy and paste buttons (ctrl+x,ctrl+c and ctrl+v) will work in powder toy. use "s" to make a stamp and press "k" to open stamps library. Hold control and use the buttons below to local save to your computer and open local saves. Hope this helped!