Some news outlets seem to have absolutely no idea how to talk about Chelsea Manning, who was known until last week as Bradley Manning and has been sentenced to 35 years in prison after she sent classified documents to wikileaks. They're confused on how to describe her actions before she announced her social transition and which pronouns they should use to talk about the period in her life when she identified as a gay man.
(hint: see previous paragraph)
Chelsea Manning is already famous under a different name, so it's fine to mention her former name. But really, don't get cute about pronouns. It is more confusing, not less, to have a jumble of 'he's and 'she's. You know from her press release that she wants to go by 'she', so use 'she' whenever you're writing about her, no matter what period of her life.
If you want to talk about something inherently gendered, then you might want a wee bit of vocabulary. She identified as a gay man for a while, meaning that's what she told people she was. Other people at the time read her as male, because that's how she presented herself. If 'read' is too jargony, try 'viewed', or 'perceived.'
You can talk about her childhood, but again, avoid being cute about it. For example, if you want to use the word 'boyhood', is there a good reason for it? Is it somehow very important to the sentence or is it a word she used herself? Don't project gender unless you're using the subject's own words or unless its needed. 'She was a quiet child' is fine. 'She was a quiet boy.' is confusing and unnecessary. 'She seemed like a normal boy.' is ok for two reasons - one is that the gender is an important part of the sentence. She didn't just seem like a normal child, she seemed like a normal boy. The other reason that it's acceptable is the word 'seemed.' She was perceived as a normal boy, which is about how she was viewed, not what she actually was. 'She was a normal boy' is not ok because it is factually incorrect (she already knew she wasn't really a boy) and because it's confusing and because it's contrary and coercively assigning a gendered identity that the subject has not assigned themselves.
In summary, use 'she' all the time. If you have to use gendered terms to refer to the past, put wiggle words around it: seemed, appeared. (I'm sure journalists are well familiar with such words.)
If Manning keeps making headlines, at some point, it will become appropriate to drop the "who was previously known as Bradley Manning," much like it's no longer necessary to mention Wendy Carlos's former first name. The point of mentioning the old name is not to draw attention to it, but to ensure that the reader knows who is meant.
Normally it's rude and somewhat irrelevant to talk about the medical aspects of a person's transition. However, because Manning is going to a prison that has specifically said it plans to violate her rights with regard to appropriate treatment, it's definitely on topic in this case. Manning has said she wants hormones. She has not said that she wants surgery. It is not necessary to mention that she doesn't currently want surgery. At some point, the repetition of this fact may become problematic. While media likes to make a big deal of 'the operation,' the reality for trans people is that hormones are much more important and that there is not one single dramatic moment during which transition occurs. Not all trans people have operations and there are a variety of operations available, rather than a single, monolithic process. The discourse around 'the operation' is a media construction. Which is not to say that trans people don't often need operations, just that the context has been distorted in popular culture. This distorted context can cause statements about anyone's lack of plan for surgery to make them seem as if they lack legitimacy or authenticity or further other them. Most trans people start out by seeking hormones and don't immediately make further plans. Therefore Manning's statement is entirely unremarkable and should not be treated otherwise.
Finally, and this should be obvious, people have a right to their gender identity that is inherently their own human right, unconnected to whatever else they've done in their lives. Whether you think Manning is a hero or a traitor, the only correct way to refer to her is through her current name and pronouns, as she has publicly requested.