I'm very methodic and before starting a new game I typically have an idea of the kind of story I want to create and what I would like my Sims' lives to be. So my gameplay tends to be coherent with their character and storyline, and very focused on that direction. I leave room for surprises, too, but in general I tend to direct more than leave it to chance or whim.
That means I won't make my Sims waste time on activities or skills that are not "in character" with them, or "just because". For example, my Sim won't be romantically involved or have children unless this was part of the narrative, or join a career unless that career is coherent with their "story". Or go to restaurants and try experimental food if that is not a significant, relevant element of their character - or visit the jungle in Selvadorada unless they are genuinely invested in it (an adventurer, an archaeologist or relic hunter, or any kind of backstory that would justify the trip... e.g. I once had an occult go there in hope to unravel the mystery of their past).
This way I keep each Sim interesting and unique. I have many saves and many different Sims in each save, in some they interact with each other, in others they don't. There's lots of variety so that still allows me to try out the many different tools and features of the game, without making it chaotic or overwhelming.
