How you express your gender if of course, a part of your identity. Gender is a myriad range of expression, not only just "masculine" or "feminin" but a whole range in between.
How we view our gender is how we view ourselves, and a part of our identity is our daemon, so daemon and gender expression are related.
Does having a daemon the same gender as you mean you're homosexual?Edit
If I had a penny for each time someone has asked that question, someone would probably be a millionaire by now. It's all in good intentions, however and I'm willing to answer.
The short answer: no.
The long answer: no, because who you have sexual intimacy with (or lack thereof) doesn't have anything to do with your daemon's gender.
My daemon doesn't have a gender, am I normal?Edit
Yes, of course! (that being said, being weird is fun but that is for another time). Daemons can have whichever gender expression the daemian desires, and while most daemons are "male" or "female", there are many daemons who do not have a gender, or have a gender which does not conform to this. This is called "non-binary".
I've discovered that my daemon's now changed gender! Should I be shocked by this?Edit
No, you shouldn't. Gender identity and daemonism is all about discovering yourself, and having a daemon that has changed gender is definitely not a bad thing. In fact, you may be discovering more about yourself in the process. It's also very common.
Is it true that your daemon's gender expresses a side of yourself you do not show?Edit
This can be (but is not always) the case. There are many people with daemons the same gender as themselves, many with non-binary and many with opposite. This, as always, depends on the individual and no one should be critisized for any gender their daemon possesses (or lack thereof).
Why are most daemons the opposite gender to their daemian?Edit
We do not know why. This may relate to the above, as in the side of yourself you may not show or something you wish to show but for personal/societal reasons cannot. Philip Pullman explains this in The Golden Compass series. Why is there gravity? We may never know, but we accept it and are glad that it exists (because you know, we wouldn't want to eat a sandwich in space).