Go to the website
www.costco.com. 
Find the link that says Photo.
Now click Log into Photo Center.
I'm going to create a log in for myself. If this is
your first time you will have to as well.
Click on Create a new album.
Give a name to your new album.
Click upload to this album.
Click I agree with anything that may or may not pop up.
You may be asked to follow some instructions on the screen read the instructions and then follow them to install whatever you have to.
Click, Click here to add your photos.
Select the pictures you want by clicking next to the
picture. Then click Add pictures.
Click Start Upload.
Click in the boxes to select the pictures that you want to
print.
Click Order Prints.
Click Add to Cart.
My Printing prices are on the right.
Click Continue at the bottom.
Put in your membership number and phone number.
Click Pick up at Warehouse or have it mailed.
Tell them what Warehouse you want to pick up at.
Review your order and click Place Order.
Click done at the bottom and you can exit.