Mixing recessive and dominant traits

[Mendel's Balls]

if you breed a spider to an albino and your spider is a het, you will get roughly half of the babies that are het spider (which do look spider since it's dominant) and all of them are het albino. SO.. breed any of them that is a spider spider back to an albino, and you will get half that are albino and half of those albinos could also be spiders. I'm not sure of the odds that any given egg has both mutations (too much math for this time haha) but there is the chance.

The probability of a spider albino resulting from a cross of a Spider het albino (SsAa) to an albino (ssaa) is 25% (.5 x .5=.25).

Like shelby said....
The easiest way to start the process is to cross an albino to a spider. Take the Spider offspring from this cross, which will all be hets for albino, and breed them back to the orginal albino parent (this is called a backcross).

If you draw the punnet square, there are four possible types of offspring from the backcross.....A Spider,An Albino Spider, A het albino, and an albino.

Hope this helps...