Hitting the Serve and Volley can actually be pretty easy. It takes practice, lots of it.
This is my personal theory:
2 most important factors:
1. Picking the right time to serve and volley. Most players want to serve and volley therefore they resort to it on most serves. You must be smart with your serve and volley. For example if you plan on serving and volleying, accidentally hit a crappy serve, you must realize this and stay back. The situation plays a great role in your ability to serve and volley.
You say you can serve, and you say you can volley, but putting them together is completely different. It is more important that you know your opponents return pattern. If you bring them out wide, where do they ussually hit it? (generally it doesnt change too much, people like to stick with whats comfortable).
2. Point of your split step: This is extremely important. Your goal is to get as close to the net as possible, but...sometimes you cant. You must hit your split step just as he is about to make contact with the ball. This should give you enough time to set up for a good volley.
Just a few tips. Serve up the middle to cut off their angle. if you can get close to the net, this is extremely effective. You can serve and volley out wide, but make sure its a hell of serve and you are covering the angles!!
Yes, slow down your serve so you can get in quicker and closer (dont be an idiot though, if he is wrecking your slower serve, stop serving and volleying haha)
Make sure your not falling forward when you hit your volley. Running into a split step means your weight needs to be back on the split step so when you come forward for your volley you will be in control.
Here is a decent article: Read More about the Split Step!
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