So I've come out to my family and it's gone okay.... we had a big argument about whether I should tell my little brother (he's about 11). Without telling him it would have been impossible to use proper pronouns. After reasoning with them that all I was going to talk about was gender (my parents were a bit concerned it would lead to
the talk) I'm allowed to do so.
I've yet to tell him because my dysphoria with pronouns and everything comes and goes and I've been feeling better after the talk with my parents so it hasn't bothered me enough to be ready to tell him. Plus he's very easily distracted and I have to wait for the right moment. I also need to think out what I'm going to say.
I'm thinking something along the lines of...
I have to tell you something, I have a disorder (or I don't know what word to use. I don't want to call it a problem)
I'll ask him if he knows what gender is... then I'll tell him I feel like a boy. There's something different with my brain and it makes me a boy. (I strongly believe the biological cause of being trans is right, that a combination of pre-natal hormones and/or genes are what causes it)
I don't know how far in depth I should go about hormones and mentioning any other stuff, such as intersex people (which would help to explain things such as gender and body not matching), and genderqueers / non-gendered people (I am technically genderqueer, but I lean so much towards the boy side that it's not too confusing) etc...
For some strange reason I remember knowing from when I was very little (8-10) that trans and intersex people existed. I don't know if my brother might. He is a very smart kid and loves to watch the discovery channel and all that stuff....he's very scientific so I don't know. Maybe I should try to explain further only if he's not getting it or asks questions.
And in the end I'll ask that if he feels comfortable to start referring to me properly and he can try to start calling me by my new name and that if he has any questions he can ask. That he doesn't have to inform his friends or anything. He can still call me his sister around them. I don't want him getting bullied or anything for this.
Any tips on what I should mention and how I should do this. Best way to explain this?

Do you think what I have planned out is okay?