Paperweights are a great way to display your needlepoint!   Your stitching always stays safe beneath the glass and as self finishing goes, you'll be hard pressed to find an easier or less expensive option.  

I get glass blanks--along with the mounting cards--from Photoweights.com.  My Dollar Sign canvas is sized specifically to fit the Large Rectangle kit (4.5 x 2.75 inches), but they have many different sizes and shapes.  The usable space is generally pretty small, but you can measure out many canvases to fit, or design your own (check out the Charts section in my shop for letters you can use to design your own monogram).  

Here are my guidelines for how to assemble your needlepoint paperweight:

1.  Stitch your canvas.  Keep in mind that the glass paperweight acts as a magnifying glass--no pressure, but you might want to keep those stitches neat!  And remember, this is a great opportunity to use fancy stitches.  They will show up beautifully under glass and will never be in danger of snagging on anything.  This is self finishing, so if you are stitching in hand (or if you are a tight stitcher like me), you might want to consider blocking your canvas.

2.  When you are finished, cut the canvas right next to stitching, all the way around the design.  This part is scary--be brave, you can do it!  Cut close, and try not to nick the thread. 

If you nick the thread, or cut all the way through, all is not lost!  If it's a tiny cut, I just ignore it--you're going to put the canvas on to something sticky and sandwich it tightly, so it will be very hard to notice in the finished product.  If the cut is deeper, you might try a little Fray Check or Elmer's glue (or something else that dries clear) on the back.

3.  Get the small adhesive mounting card.  It's sometimes not marked clearly, but there is a paper over the card that will pull off to reveal the sticky side (bending the corner a bit will help you grab the paper).

4.  Stick your canvas to the card, right side up—the back of your canvas goes on the sticky side of the card.  Start at one short edge, placing one corner in place, then the other, then wiggle the canvas as needed to ensure that it is straight. Pull the canvas straight and slowly adhere the canvas to the card keeping it as even as possible.  Try to cover the card entirely.  Firmly press the canvas to the adhesive card. 

5.  Before you put the canvas into the glass, look at the front of your canvas.  Make sure any stray bit of fluff or lint is removed from the front and brush any bits off the sides--or they will be forever encased in your paperweight and annoy you every time you look at it (ask me how I know).  Similarly, make sure the inside of the glass is clean and free of fingerprints. 

6.  Place the canvas into the glass blank, centered and neat.  There will be a little bit of bend to the canvas at the corners--this is totally ok. 

7.  Peel the paper off the black flocked base paper.  Start at one short end and slowly press the backing to the glass, checking that the needlepoint is still straight on the inside.  

Here is the side view of a finished paperweight showing the cut edge of the canvas--you really don't see it in the reflection of the glass:

And you’re done!  Enjoy!

Another finishing option: 

I have not done this, but you might be able to do a binding stitch on the edge of the canvas and then affix it to the mounting card.  There should be enough depth inside the glass blank to accommodate the thickness, but be mindful not to make the edges too bulky.