They should automatically post to your account. Sometimes you need to read the 'small print' to notice that the points won't be available until a certain date or only on certain purchases. Your receipt should tell you how many you earned, including bonus ones for purchasing certain items, and you can call a SYW customer service rep. to have them post.
Check 'My Orders' and you can see a detailed account of earned points.
P.S. Even if it doesn't post automatically they are really good about fixing.