Surf where the waves are
Back when I was a young and carefree fellow, I was an enthusiastic member of the canoe and kayak club at Plymouth University. Plymouth, with it's deepwater port and Royal Navy dockyard had a breakwater, but a decent amount of swell for kayak surfing got through and if we wanted even more, we could go outside of the breakwater and find plenty of wave action. All of that was true except for when it wasn't, because the sea is almost completely unpredictable. If the conditions were right, then there was "all you can eat" surfing conditions, otherwise the water would be flat and totally unsuitable for surfing.
Plymouth (the one in England, not the roughly 30 Plymouths in the United States named after it) is in the county of Devon. Right next door is the county of Cornwall, where I am from. Cornwall is easy to find on a map of England as it's the pointy bit down in the bottom left corner. Cornwall extends out into the Atlantic Ocean and to the south is where the English Channel meets the Atlantic Ocean. This gives plentiful opportunities for good surf conditions. Some of the waves rolling in from the ocean are big enough that Cornwall is a world renowned surf location.
With the unpredictability of the surf conditions around the coast, the local radio stations have surf reports, where they announce where the waves are around the coast. For the dedicated surfers in the area, they listen to the report and then drive quickly to where the waves are. Because if there's one thing that all surfers know (even us humble kayak surfers), you need waves to surf on, so they will drive to wherever the waves are. This is a fundamental rule of surfing. No matter how much you may wish otherwise, an absence of waves means that you are not surfing. If you want to surf, you go where the waves are. Don't bother complaining, go where the waves are.
Let's take this analogy into the realm of the spiritual. Those of us who wish to genuinely please the Lord want to be in his will. The best way to do this is to get involved in an existing successful ministry. A successful ministry, like the waves that we already talked about, is a sign that conditions are good for ministry because the Lord is moving at that time and in that place. (Some are called to start new ministries in new places, but that's not the case for most people.) If you have time, energy or other resources to spare, the way to be the most useful in ministry (after ensuring that you regularly and faithfully attend your home church and pay your tithes) is to put that into a successful ministry. There is not a legitimate ministry in existence that can't do more good works with the addition of helpful people or resources.
So, surf where the waves are and minister where the Spirit of the Lord is already moving!