Growing from seed
Although there are other methods of starting a Lithops collection, growing from seed is by far the least expensive and the most rewarding. Some species/subspecies can be much more difficult than others but a mixed lot will give you an excellent start with very little disappointment. Apart from seeds, divisions of mature plants and adult plants will give you instant results however they are much more expensive and often very difficult to obtain.
There are a few methods of growing all cactus and succulent seeds and the one we use may not be as successful for you as it is for us. We suggest that you search with Google for "baggy method for seeds" which invloves the use of "zip lock" bags to create humidity. The type of substrate used for seeds can vary considerably, depending on your particular situation, but we DO NOT recommend the use of "paper towel" nor "cotton" as a substrate as when you come to potting up your seedlings you will have great difficulty.
For a comprehensive "guide" to starting Lithops, you can download a document in Word format (for your own personal use) that contains more information about materials, pots and growing conditions HERE.
There are other sources of information too and we suggest that you have a read of the following two articles, both of which contain very good information:
worldofsucculents.com/growing-cacti-seed (Opens in a new window)
Here's a very good site by a novice grower that really does already know what he's doing:
lithopsblog.wordpress.com/ (Opens in a new window)