Amy, Zoe has it right, just click on the link in my post #16
Name change and title can be changed in a number of ways, however, a deed poll is by far the most common way. Gender markers on a number of documents can be changed as I've posted about, however, the legal change of gender is not complete without a GRC.
Within the UK we are fortunate that to be considered TS, with its protection under the equalities act, we do not have to undergo surgery, and that is reflected in the link.