Mac owners might well be fortunate enough to use one of the most beautifully designed user interfaces, but every now and then a sea of blue folders and standard document icons makes it a little hard to see exactly what file or folder you’re looking for. Fortunately, following the four steps below will allow you to create your own custom icons for your files, folders and apps, enabling you to easily find what you’re looking for (or disguise that hideous-looking app icon). You’ll need an icon-like source image (you can either create your own or find some online) and all the tools you need are part of OS X itself. Once you’ve got that, it’s time to get creative…
Find your replacement icon (transparent PNG files work best) and copy the image itself using the Edit menu or Command+C on your keyboard.
Click on the file, folder or app whose icon you want to replace, head into the File menu and choose Get Info or hit Command+I.
In the Get Info window that appears, click on the existing icon in the top-left corner and ensure that it’s highlighted with a blue glow.
With the old icon highlighted, head into the Edit menu and paste in the new icon image you copied earlier on to finish things off.