I'll second what Ian said, their stands and also the printer version are the best way to go.
Here's something i do to get the screens lined up PERFECTLY by yourself, the FIRST time:
Take a piece of WHITE cardboard, don't have to be very big, just big enough that you can cut a slot in it wide enough to slip over the stock above the grip or butt while gripping it so it stands up vertically behind the scopes occular lense and you can see white through it when out at the screens adjusting them.
Set the power ring on the scope to max power (though this won't make any difference if the crosshair is in the first focal plane) and line up the crosshairs on the targets bullseye, now don't move the rifle.
Now, with your eyeball looking back through the scope tube from the center of each screen, line up the vertical crosshair that should now contrast very well with the white background with the center of the MUZZLE and move the screen left or right to center the bore line over each screen. I use my finger held out up above the center of each screen as a kind of sight if needed. Helps to first get the screens roughly adjusted so the bullet path will be 6-8" above end screens, do your line up then go back and get the rail as parelell to the bore line as possible, then double check alignment again. If everything is perfectly aligned looking back from the screens to the bore and crosshair, it will be perfect when you look back through the scope on low power. You may have to tip the rifle forward keeping the vertical crosshair on the bull while verifying it's in the center of the screens, just depends on how low you like to set the screens and how low of power setting you have.
Once the rifle is setup in the rest, I can have the hight and alignment of the screens set and ready in less than a minute, quite a bit faster than running back and forth looking through the scope each time an adjustment is made to a screen, which on the other hand can be quite time consuming. Not to mention other people at the range will probably be "waiting" on you, hoping to shoot... sometime this century.