To get the image larger,
First make sure you have made enough room on the page (stretch the 'white' area, before you paste, using the little white square)
Then once it is pasted in, you will see the image is bordered by a dotted line (like the text box from earlier).
While this border is in place you can still adjust the image.
So you can stretch it manually using the little white square (to a maximum of the page to have allowed), or use the resize button (see below)
.
click the resize button, and adjust the number (to make it bigger by 10%, then use 110)
Be aware that if you make it too much larger than the original, it will become grainy (experiment with it)
when you have enlarged it to what you want, click somewhere on the page to confirm it, and the dotted border will disappear.