Sprinklers change farm planning because they turn watering from a daily labor constraint into a layout problem. That frees time and energy for mining, fishing, relationships and expansion.
Coverage comes first
Know exactly which tiles the sprinkler waters before planting around it. A clean repeating layout is easier to maintain than scattered coverage.
Upgrade timing
Do not replace every sprinkler immediately when a better tier becomes available. Upgrade the areas where increased coverage saves the most space or daily work.
Design around crop blocks
Regular crop blocks make planting, harvesting and pathing easier. Leave enough room for movement, scarecrows and machines instead of maximizing planted tiles at all costs.
Use freed time intentionally
The real value of sprinklers is not only water coverage. They create time for the Mines, fishing, Skull Cavern preparation and other progression systems.
Connect sprinklers to crop planning
Once watering is automated, crop selection can focus more on growth time, regrowth and seasonal deadlines. Use the Crop Planner before committing a large automated field late in the season.
Source: Stardew Valley Wiki — Sprinkler.