Kids at three like to feel they have some control even though they really aren't ready for a lot of control yet.
First, I suggest having a schedule or routine everyday that is predictable and even posted for your child (using pictures). Having it be predictable for your child when getting dressed will be required actually helps him feel "in control." If he needs a reason for getting dressed, have an "outside time" set sometime mid-morning (before you would normally go out) that he must get dressed for and then keep him dressed from that point on in the day. Perhaps you just go for a quick 5-10 minute walk, maybe you kick a ball around the yard, but going outside is a reason to get dressed.
Second, use warnings - i.e. Getting dressed time is in 10 minutes. Now there are only five minutes to dressing. In two minutes you need to get dressed, I'm going to set the time for you and when the buzzer dings it is time! . . . Knowing it is coming helps him transition from his favorite nakedness to his less favorite, wearing of clothing.
Third, if you don't already, allow him some choice in what he has to wear. At this age giving him all the choice will just be overwhelming and work against you, but if you set out two shirts and ask, "which one do you want to wear." You are offering him a sense of control even while he really has no say in anything important about what he is wearing, when etc.
Finally, make a game of it. "(child's name)," put the pants on your head like a hat, "Is this how you wear pants?" . . . "no? Oh well, show me wear they go." You can also put socks on your ears, start to encourage him to put a foot in a sleeve. . . You get the idea. Laughter often gets them going.