SLA approach to learning reading/writing?

I am Deaf so learning to speak/hear a spoken language is not a priority for me. However, I do want to be able to read and write fluently so I can communicate via writing. What do you suggest as a comparable SLA approach for acquiring reading and writing competency? With spoken language, you start with listening and conversation. How does that work best for a reading/writing competency when you are starting to learn the language from scratch.