I'd offer to help, but I had the opposite problem. When my phasing first manifested, it would just happen whenever it wanted to, whether I was trying or not. A lot of the time, it felt kind of random. It took me a while to figure out what made it work for me.
[She considered it for a moment.]
So, you have all the same powers as your uncle, right? In theory? Has he ever talked to you about phasing or your shared powers in general?