How can I refresh my living room on a budget with DIY art and shelves?

[LukeC]

I'm trying to refresh my living room on a tight budget and want to tackle a few DIY decor projects, like creating a large-scale abstract painting and building floating shelves, but I'm intimidated by the potential for it to look obviously homemade or mismatched. I have basic tools and some painting experience, but I'm not sure where to source affordable, quality materials like good canvas or sturdy brackets. For fellow DIY enthusiasts, what beginner-friendly projects had the biggest visual impact in your space, and what are your tips for achieving a polished, cohesive look without professional-grade skills or equipment?