Building Custom Formulas for some actions and conditions under Client Triggers is more tedious compared to server triggers since a more intricate syntax is used (JavaScript and SuiteScript).

There is a technique for building client-side formulas easier by using the Workflow Visual Condition Builder to specify the fields to be used, then convert the built condition to Custom Formula. If the formula will be used for value assignment (i.e. for use with Set Field Value Action, etc.), the converted condition may need a little tweaking. See the screenshots below that demonstrates this technique:

Now, to give an example of a formula used for value assignment, let's tweak the formula obtained above that can be used to copy the