First, take a screen shot of the image that you're trying to host.
Use the "PrtSC" (Print Screen) button usually located in the top right of your keyboard.
This will copy your entire screen as an image to your clipboard.
Next, open up a image editing program such as Microsoft Paint, Photoshop, etc. and paste (Ctrl + V) the image into the program.
You should get your entire screen that you printed as an image.
Next, crop the image so that it is just the meme or whatever image you're trying to host.
Save that file.
Now head to a hosting website such as Photobucket, Imageshack.us, or tinypic.com.
If you're looking for a portfolio of saved images, Imageshack is the best. But you have to sign up. If you don't care about saving them, go to tinypic.com. Browse your files and upload the image. The link will be at the bottom for 'Direct Layout'.