I just found out that friend of mine sharpens his chef’s knife once a week(!)
Assuming you’re not abusing your knives by cutting on hard surfaces or tossing them in a drawer, you shouldn’t need to sharpen them very often at all—to reestablish a beautifully sharp edge, you just need to hone them regularly. Some chefs hone their knives before every use!
Here’s a tutorial from Consumer Reports:
If you do need to sharpen your knives (for most home chefs, you’ll probably want to do this a few times a year) they also have a very thorough guide to the many available options.