Your diagram tells a story:
Layout: Left to right flow. Users on left, databases on right. Group related components.
Labeling: Every box needs a name. Add protocols (HTTP, gRPC). Show data flow direction with arrows.
Space management: Start in the center. Leave room to add components. Don't cram into corners.
Colors: Use different colors for different concerns (data flow, failure paths). Not required but helps clarity.
Virtual whiteboard: Practice with Excalidraw or similar. Screen sharing adds latency. Draw slightly slower than in-person.