There's not much training at staking when it comes to combat techniques unless you do some kind of hybrid dueling. If you're after style swapping which is quite questionable if it even does affect one's fighting in any way, you're going to get that covered even at fighting npc's.
There's not much practicing here either because getting the first hit is determined by the system. Assuming that you're skillful enough to click the opponent (spam clicking will work too)