Consulting is a bit too broad of a concept to provide a "what does a consultant actually do" definition. Anything that people will pay you to tell them or do for them without making you their direct employee is, technically speaking, consulting them.

For example: reviewing someone's database configuration and providing general recommendations for improvement is consultation, but so is directly modifying those settings for them and not actually telling them what changed. The expectations and deliverables are set by agreement between the consultant and the consultee.