adnanxsg

Cheapest option is to download a free landing page design and code it: https://www.sketchappsources.com/

A better option is to purchase something off of https://themeforest.net/category/site-templates

its usually pretty cheap (sub $100) and the quality is pretty high.

Learning to design your own is harder. I'd say start with something from the resources above and iterate as you optimize for specific goals. As you spend more time optimizing your product you'll see design patterns being used by your competitors and learn along the way.

I think on hiring threads freelancers are looking for paid gigs. I'm just offering a free redesign for projects that cant afford to spend money on that (eg. open source projects with limited budgets)

I'm particularly interested in how you do about understanding the problem in more details, brainstorming solutions, working with your peers and getting feedback/review, and finally what the final set of deliverables are.

You'd generate ideas by trying to uncover problems that your target audience faces. You can do that by talking to them - or if thats not possible, just doing a lot of the secondary research, or even just observing existing behavior and seeing what has the most friction.