How to Draw a Good Diagram of a Business Workflow?

Recruitment (hiring) process.
"Recruitment refers to the process of attracting, screening, selecting, and onboarding a qualified person for a job. At the strategic level it may involve the development of an employer brand which includes an "employee offering".
The stages of the recruitment process include: job analysis and developing some person specification; the sourcing of candidates by networking, advertising, and other search methods; matching candidates to job requirements and screening individuals using testing (skills or personality assessment); assessment of candidates' motivations and their fit with organizational requirements by interviewing and other assessment techniques. The recruitment process also includes the making and finalizing of job offers and the induction and onboarding of new employees.
Depending on the size and culture of the organization, recruitment may be undertaken in-house by managers, human resource generalists and/ or recruitment specialists. Alternatively, parts of the process may be undertaken by either public-sector employment agencies, commercial recruitment agencies, or specialist search consultancies." [Recruitment. Wikipedia]
The BPMN 1.2 (Business Process Model and Notation) diagram example "Hiring process" was created using the ConceptDraw PRO diagramming and vector drawing software extended with the Business Process Diagram solution from the Business Processes area of ConceptDraw Solution Park.