The traditional way to influence the order in which requirements are implemented or tasks are done is prioritization. Set a priority on a requirement or task, sort the backlog or board by priority, and take the tasks from the top, that is, the most urgent ones. ALM has a predefined priority list, which can be changed in the administrative section.
The priority color scheme is used when a priority is shown on tasks and requirements, and when cards are drawn on boards.
An alternative way to order work is to number it. Every requirement or task has a "Number" field, whose value increases automatically when the item is created. Use the sort settings to order tasks by number. On lists or boards you can drag rows or cards, which interactively changes their numbering and order, and therefore the order in which they are done.
Sometimes the order of work is affected by dependencies between requirements or tasks. One example is a process dependency: the work cannot be done until the previous work is finished.
To set dependencies between primary requirements, use the "Links" field. Create links of the type "Blocks". In the requirements lifecycle settings you can use preconditions on transitions that check whether blocking requirements are complete. If a requirement is not complete and it blocks another requirement, the second requirement cannot be started or completed.
A requirement can also be blocked without creating another requirement. For example, if open questions prevent the work on the requirement from moving on. Choose the "Block" action and select a reason from the reference list. You can add your own reasons to the list, and build a chart from it of why requirements on the project are blocked.
For tasks, you can likewise use the "Predecessor tasks" or "Successor tasks" fields to record dependencies and use them to configure the task lifecycle.