When your child is ready, move on to pencil and paper. Build confidence by letting your preschooler trace simple lines and shapes, then proceed to letters. You can eventually teach your child to write his name by letting him trace or copy it daily. If your child needs help remembering how to spell her name, practice with fridge magnets, letter tiles or alphabet blocks.
These are basically digital versions (like ebooks) of worksheets that can be bought and downloaded to your computer from the internet or from CDs and then printed out. The advantage is that you can print out whichever sheet you wish. If you need to re-inforce a certain concept more you can usually print out that sheet again. Of course you will therefore need to have a computer and a printer.
Worksheets that include topics such as social and natural science will help to expand your child's horizons, teaching them about their environment and how things work, while improving their vocabulary at the same time. A worksheet about farm animals can initiate a visit to the farm area at the zoo, or to a real farm, where your child can explore and learn even more.
This sounds like an awful lot, doesn't it! A good set of preschool worksheets should cover all of this, and more. In the preschool years, repetition is the key to learning, but you should look for worksheets that teach the same skills in a variety of ways. This not only prevents boredom setting in, but also reinforces the concepts by encouraging understanding as well. The importance of reading to your child cannot be emphasised enough, and you should encourage them to 'read' as much as possible too.