We started with a 3' by 5' deck. Call that a balcony, since it doesn't really deserve the term "deck." You could stand on it, but that was about it. I knew it had to change.
The planning process took several months. Having never built a deck before, I wanted to make sure I knew what I was getting into. I went around and looked at different decks just to see how it was done. I watched a lot of videos and did a lot of reading as well. I called several people in the industry and chatted with them about their experience, the types of materials are most common and what would add the most value. I also talked with the city inspector several times in order to figure out what their requirements would be and what I needed to do to get my permits.
So all of that might have been a bit of overkill, but it gave me the confidence I needed to move forward. Every time I looked at another deck, I knew all of the little nuances that might not otherwise be obvious and I could tell myself, "Yeah, I can build something just like that."
We started to price it out. Originally I had planned on building an all wood deck. It was just more economical. My dad was a big fan of composite material though, and kept suggesting we use that instead. From all my discussions as well, that seemed to be the consensus of everyone, so I relented. It would be at least twice as much, but the value it would add would make up for it. The composite decking would of course end up being the most expensive portion of the deck (followed by the railing, then the stairs and finally the frame), but certainly well worth it.
I made all of my detailed plans (portions shown below) in order to get the city to sign off. Turns out they only needed a few numbers and a check, but it was good to have it all drawn out, though the real plans were all detailed out quite well in my head. Once the planning was complete, it was time for the execution.