It’s a delight to find these in a cryptic crossword puzzle. It’s like when you’re standing in a really long line at the grocery store and then, just like that, a new line opens up and you get to zoom in and be served first. But like the new line at the grocery store, the first/last letter clues are rare. In a first or last letter riddle, you get the answer by taking either the first or last letters of the words in the clue (excluding the definition portion of the clue). Yes, it’s that easy.
How do you know it's that kind of clue?
As with other clues, there will be a tip-off word. In a first-letter clue, the words “first” or “initially” will appear. Other tip-off words include “start off” or “leader” or “head of”. The tip-off that you’re dealing with a last letter clue is a word like “last” or “ultimately” or “final”.
Is there anything else that tips you off?
Actually, yes. The number of remaining words in the clue is important because if it's a first- or last-letter clue, the number of words must add up to the number of letters in the answer. In the example above, the word “leader” means that you’ve got a first-letter clue. The answer is either "time" or “denigrate”. (I'm giving it to you: it's "denigrate".) Count up the words on the right and you'll see that there are five of them -- perfect!
In order to get the solution, simply take the first letters of “reaching out a second time".