Yarn over (YO) hook, insert hook in stitch (st), pull up a loop (lp), 3 lps on hook. YO hook, pull through 2 lps. YO hook insert in next st, pull up a lp, 4 lps on hook. YO, pull through 2 lps, 3 lps on hook. YO, insert hook in next st. YO, pull up a lp, 5 lps on hook. YO, draw through 2 lps, 4 lps left on hook. YO draw through all 4 lps left on hook.
(see photos for dc2tog for beginning)
last 4 loops left on hook, draw yarn through all loops
Here's a hint, for the last time you pull the yarn through on a dc together st, there will be one more lp than sts you are bringing together.