Open Blender
Delete the cube by pressing X and then choosing delete.
Click SHIFT + A to open the add menu, and then at the top, under mesh, and choose A UV Sphere
Shift + A to open the add menu, and then at the top, under mesh, choose a plane
Your scene should be this:
Example:

Now click on the blue arrow to align your plane right on top of your sphere
Should look like this
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Now press the number 7 key on your keypad to go to the top view
At the bottom toolbar you will now have a few buttons to click. The image below shows the ones you need to check and change.
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As you can see in image one, you click on the horseshoe.
Image two you will choose FACE and it will open up more on your toolbar
Image three you choose the one that is outlined
Press the S for resizing the image, and resize the plane/square so that it fits right to the corners of the sphere. Corners on a sphere? lol... Here's the example
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You have have to scroll your mouse and move the arrows to get it lined up just right...
Okay, when done, tab into edit mode, or choose edit mode from the bottom toolbar. Then press the Z key to go into wireframe view. You can also change that from the bottom toolbar.
Image now should look like
Example:

Now when you resize it, make sure you rotate it to see that the plane/square is on top of the sphere. I noticed in wire view that I had to make more adjustments. So make sure it's lined up and resized so that it looks like the image I have shown. Here's a side view to make sure it's correct
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Now go back to top mode (number key 7) Hit the W key, then choose, at the top, subdivide. Do this about 3 or 4 times. Then press the G button and then LEFT click. DO NOT MOVE THE MOUSE WHEN YOU PRESS THE G BUTTON AND CLICK.
Now here's my image and what it looks like:
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Notice how one of the edges didn't snap to the sphere? You just have to click CTRL Z to go back one step... then resize your plane/square until your image looks like this: *note* you don't have to repeat the G and Left Click. Just keep going back one step, resizing, until your result is this:
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See now it's nice and snug on the sphere? YAY lol
Now you can click tab to go back to object mode and select the sphere and delete that puppy. And your scene now looks like this
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Now it looks funky LOL. But we can use this to make different type object. Let's go ahead and finish this so that we have something created.
Go back to edit mode and make sure you have your new image selected. Should look like this
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Press the E and bring it straight down
Press S to size it and Z and bring out the edge a bit.
Press E to extrude it again and go straight down.
Press S to size it and Z to bring out the edge a bit until the bottom is now square.
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You can do all sorts of things with this technigue. Just a few qickies....
Example:

Example:

Maybe the first one could be the start of a ship? Maybe second one a robot? lol. Who knows, but it's limitless!
Your image is like this now, but without the door and the color


Hope you enjoyed.