Ch(di) paillage de plantes au jardin - besoin d'aide

I need help with plant mulching in my small garden. The area is roughly 6x4 meters and currently bare soil. I’d like to mulch the flower beds and perimeter with natural mulch to suppress weeds, retain moisture, and improve soil health. Preferences: use untreated, organic mulch (pine bark or composted leaf mold), keep pathways clear, and avoid heavy machinery. I’d love guidance on mulch depth (about 5-7 cm) and timing. Please bring a wheelbarrow, rake, and gloves; I can provide mulch if you have a delivery option.