How can I without my mom getting suspicious about everything, or telling me that I can't be that way?
Well I think the real reason you're asking this question is probably because you realise that this is an impossibility. You can't suddenly start trying to become more androgynous without raising some suspicions. But what you can do is talk to your mom about it. Are you out to her? If not, you definitely should start thinking about it. It may take a while for you to get your head around it, but it's most likely the only way you can do something like this.