How to convey order of a list matters (and allow reordering)

Question

We have a an application with a list of rules (probably no more than 10) that a user defines (plus some default one):

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Every rule has a condition it checks for, and some action it preforms when the condition is met.

Logicially, The rules have an if/then/else or Switch/case relationship. This means if you switch the order of the rules it can have significant impact on what will happen. However we've had a hard time conveying this idea to the user (particularly if they dont click on the little help bubble).

Is there a standard pattern to do this?

Answer 1

One way i would represent this is to use a waterfall pattern. In a waterfall methodology, current step flows into the next step and so on. So, if you could display the stacks indented (like reply to comments in a blogpost) it would instruct the user that the preceding rule is executed first and its output is fed to the next rule. Hope this helps.

Another simple alternative is to use numbering.

Third option is to use pointed arrows between stacks to indicate the flow.