Make sure you have not only an idea, but an idea of how to execute those ideas. I believe you should focus on one of them although this is based on my preference for sequential-like implementation [0].

If you're still pressing ahead of parallel;

1) keep excellent documentation that even a hired programmer can follow.

2) ensure you don't forget to eat, drink, exercise, etc. Fixed habits help tremendously.

3) have a plan to cope with information overload. eg, HN is full of links that help your project and your project ideas. My plan is that unless the links are very very good, you're already implementing it. You could bookmark it as "Research later" (tip: ensure the bookmarks are descriptive. eg Nginx security guide [1])

4) Adopt a 'write down and forget', eg logbook. A calendar is great for events.

There's more tips but I need to get back on my project.

[0] I've attempted parallel implementation, the burnout and confusion comes much faster for me despite all my tips above.

[1] https://calomel.org/nginx.html

Thanks for the detailed comment. The first idea is a task management tool. The tool I'm building is to solve a. info overload, b. task management, c. solid reminder system etc. Current tools doesn't work for my needs. So, I'm building it, so that I can maintain my sanity in future.

I have mockups done, also finished a small prototype, using that felt good. So, I'm going on with it.

Second Idea is very big, but not tough to implement. So, I'm going to try this too.

I say when you're starting, do as much as you would like to do. If you feel yourself gravitating towards one project more. Then focus on that more (meaning, be able to drop a project that doesn't interest you any more. Don't feel obligated to follow through with it.)

At the beginning I feel it's more important to figure out what you like and what's working more for you. (Kinda like dating.)

However once you figure that out. It's time to buckle down and go for the win. It's much harder to execute than to talk about. But I'm sure you can do it.

Thanks for the kind words, I think both of these products are very meaningful. Thats why I can't narrow it down to one.

I'd say go where your motivation takes you. Let's say you are burning to do idea 1 - so do it! Then you may get burnt out for the weekend and not want to do idea 1, so start idea 2.

Mainly keep it very focused, don't over-engineer, use the customer-development framework and keep refining to the very simple core of the product.

I think these things take time so you will be glad that you flowed with your momentum. In a couple months I'm sure you will gain the experience to answer this question unequivocally.

You won't get far with a mediocre product, so you have to be able to do at least one of them very well. That said, a second project can be a break from the first one. Don't let doing both distract you from doing either one well enough to succeed.

Read Steven Blank's 4 steps to the epiphany. Then rethink.