Need help fixing wall-mounted shelves securely

I’m looking for a reliable handyman to install and fix wall-mounted shelves in my living room. The walls are plaster with studs behind, and I’d like them mounted securely to support books and decor. Please bring appropriate screws, wall plugs, and mounting brackets. If possible, confirm shelf spacing and provide recommendations for avoiding common issues like sagging. I’d prefer someone who can work with precision and clean up after. Flexible with start time, but a morning slot would be ideal.