Translation is not an exact science and translators have different approaches, but this is the process I follow:
Read the document to detect specialized terms
Determine target audience (to select formal or informal tone)
Translate and create a glossary on the go, to ensure consistency throughout the document
I dictate almost all of my translations: In addition of being faster than typing, I believe it helps to ensure a natural flow of words. When you read something out loud, you can detect errors more easily than by reading.
Ask client questions to ensure proper understanding (if the translator doesn't understand something and doesn't ask, how can the audience understand the translation?)
Review the document, comparing source and target language, to ensure nothing is missing, and that terms are consistent
Read and edit the translated text to ensure natural flow and correct structure.