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Unlike classic Microsoft Paint, Paint 3D allows you to create your image on a transparent background; however, you cannot create an icon file from directly within Paint 3D. Fortunately, you can use ICO Convert to turn your image with a transparent background into a more satisfactory icon file. Click the Windows logo in the bottom-left corner of the screen. Type in paint 3d, then click Paint 3D at the top of the Start window.  Unlike Microsoft Paint, Paint 3D is only available on Windows 10 computers. Paint 3D was first introduced with the Windows 10 Creator's Update in spring of 2017. If you don't have Paint 3D, update Windows 10 before proceeding. It's at the top of the window. This box-shaped icon is in the upper-right side of the window. Doing so opens a sidebar on the right side of the window. The switch will turn blue {"smallUrl":"https:\/\/www.wikihow.com\/images\/0\/0a\/Windows10switchon.png","bigUrl":"\/images\/thumb\/0\/0a\/Windows10switchon.png\/57px-Windows10switchon.png","smallWidth":460,"smallHeight":218,"bigWidth":"57","bigHeight":"27","licensing":"<div class=\"mw-parser-output\"><p>License: <a rel=\"nofollow\" class=\"external text\" href=\"http:\/\/en.wikipedia.org\/wiki\/Public_domain\">Public Domain<\/a><br>\n<\/p><\/div>"}, indicating that your canvas is now transparent. If this switch is blue, your canvas is already transparent. On the right side of the window, do the following:  Click the "Percent" drop-down box, then click Pixels in the resulting menu. Replace the value in the "Width" box with 32. Replace the value in the "Height" box with 32. Click and drag the slider in the upper-right side of the page until your canvas is large enough to work on. Click the brush-shaped "Brushes" tab at the top of the window, then select a brush, select a color, lower the brush's size if necessary, and click and drag to draw on the canvas. This folder-shaped icon is in the top-left corner of the window. It's in the main window. Doing so opens a "Save As" window. Type whatever you want to name your icon into the "File name" text box. In the "Save as type" box, you should see "2D - PNG (*.png)" listed; if not, click the "Save as type" box and then click 2D - PNG (*.png) in the drop-down menu. Click a folder (e.g., Desktop) on the left side of the window. It's in the bottom-right corner of the window. Doing so will save your project as a PNG with a transparent background. Since your saved PNG file can't be used as an icon, you'll have to turn it into an icon file with a free website:  Go to http://icoconvert.com/ in your computer's web browser. Click Choose file. Select your PNG, then click Open. Click Upload. Crop your image as needed, then scroll down and click Select None. Scroll all the way down and click Convert ICO. Click the Download your icon(s) link when it appears. . Once you've saved the icon, you're free to assign it to a shortcut on your computer.

Summary:
Understand Paint 3D's limitations. Open Start . Open Paint 3D. Click New. Click the "Canvas" button. Click the white "Transparent canvas" switch . Resize the canvas. Zoom in. Draw your icon. Click the "Menu" icon. Click Image. Enter a name for your icon. Make sure the file format is correct. Select a save location. Click Save. Convert an image file into an icon. Use your icon as a shortcut