It's time to change your expectations or your location.
Slow WiFi is annoying. It's a bandwidth problem: how much you want to accomplish is at odds with how fast you want to accomplish it. When you have a slow WiFi problem, there are really two options: change location, or change your expectations.
If you must get the work done, and get it done quickly, you're going to have to invest time and resources into finding more bandwidth.
If you don't change locations, you're going to have to change your expectations by either reducing the amount of work or by having more patience.
Slow WiFi also presents another interesting situation. It can be used as an excuse to avoid work as we engage in the small and distracting tasks, or it can help us focus on the one important thing we want to get done. Both responses are helpful depending on the situation.
Knowing your personal tendency for how you work when bandwidth gets tight is helpful. Are you more likely to neglect the multiple and critical day to day tasks, or are you more likely to neglect the larger and time-consuming projects and decisions?
Sometimes it's best to move, sometimes it's best to have a little more patience, and other times it's best to unplug and enjoy a conversation over coffee. It's up to you, just know the trade-offs.