Many answers posted here involve finding an ID number for a custom field, or a group, or something else. How do I do that?
The easiest way is to hover your mouse cursor over a link that refers to the item in question. In the link that apppears in the bottom of the browser, look for the part that says
&id= and note the number after it.
In a few cases, there won't be any
&id=. For instance, with groups it will be
&gid=. They should all have "id" in them though! Just make sure you don't pick the wrong one - e.g. in the first screenshot above, "cid" is the contact ID, not the contribution ID.