You mention paper ides, so I will answer assuming this is about research.
In my experience, picking a good research topic up front is extremely important, since actually testing your idea in depth will take a lot of time and there’s a significant chance that once you do that you’ll have to discard it anyway. So I think a period of flipping through project ideas without long-term commitment to any of them is pretty helpful for feeling out whether a given idea is worth the time and risk. Just make sure that you really seriously consider each idea you’re trying out rather than just dropping it for something else, and write down what you’re thinking in case you want to revisit the idea later.
During this trial period for an idea, I’d suggest biasing towards feeling out what the project might look like in the longer term rather than diving directly into implementation, though doing some initial prototyping can help you learn quickly here. Think about potential impact, feasibility given your time and resources, any unknowns you think could sink the project (investigate these ASAP), anyone you might want to collaborate with, and how it might fit into a broader research landscape. Talk the idea over with other people. Try to learn quickly here, and move on freely. Understand that if you commit to a project, there will likely be months of work before any payoff.
I have also heard the advice to keep multiple projects going simultaneously, although I haven’t tried this myself. I would caution against using this as an excuse to backburner a bunch of things rather than focusing down and killing what isn’t working, though.
You mention paper ides, so I will answer assuming this is about research.
In my experience, picking a good research topic up front is extremely important, since actually testing your idea in depth will take a lot of time and there’s a significant chance that once you do that you’ll have to discard it anyway. So I think a period of flipping through project ideas without long-term commitment to any of them is pretty helpful for feeling out whether a given idea is worth the time and risk. Just make sure that you really seriously consider each idea you’re trying out rather than just dropping it for something else, and write down what you’re thinking in case you want to revisit the idea later.
During this trial period for an idea, I’d suggest biasing towards feeling out what the project might look like in the longer term rather than diving directly into implementation, though doing some initial prototyping can help you learn quickly here. Think about potential impact, feasibility given your time and resources, any unknowns you think could sink the project (investigate these ASAP), anyone you might want to collaborate with, and how it might fit into a broader research landscape. Talk the idea over with other people. Try to learn quickly here, and move on freely. Understand that if you commit to a project, there will likely be months of work before any payoff.
I have also heard the advice to keep multiple projects going simultaneously, although I haven’t tried this myself. I would caution against using this as an excuse to backburner a bunch of things rather than focusing down and killing what isn’t working, though.