Kanban requires making your work visible and transparent, which is accomplished by using a Kanban board. This tool consists of columns representing the stages of your workflow and cards representing the work items. You can use a physical board with sticky notes or a digital tool with online cards. The board enables you to easily observe the status of your work, dependencies, blockers, and bottlenecks. However, to measure your flow you need to use metrics and indicators such as lead time (time from request to delivery), cycle time (time from start to finish), throughput (number of work items delivered in a period), work in progress (number of work items in each stage of workflow), WIP limit (maximum number of work items in each stage of workflow), cumulative flow diagram (graphical representation of number of work items in each stage over time), and flow efficiency (ratio of value-adding time to total lead time). By measuring these metrics and indicators, you can get an accurate picture of how your work is flowing and pinpoint any issues or opportunities for improvement.