By the time your child is ready for kindergarten or school, they should be able to recognize their own name and other simple written words. The sounds of each letter of the alphabet should be familiar to your child, and they should understand the principle of reading from left to right, which way to hold a book, and possibly even be starting to read three and four-letter words.
A homeschooled student will receive the absolute best education possible without the expense and overhead of ordering multiple copies of hardcopy texts. Textbooks will not need to be discarded at the end each school year.
Almost everything you do with your child can be turned into an opportunity to learn - and worksheets can give you the guidance you need to find those opportunities.
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.