Le verbe "demander"

A ex-french teacher of yore, once said the hardest words in french are the little ones. He was referring to de, à, en, and others. Today's short lesson gives you the rules on how to use them with the verb demander.

Que dois-je faire pour demander une prestation ?

Source: dsc.gc.ca

Je demande à ma fille de m'aider.

Source: unknown

Grammaire
1. Rule #1
   demander à qqun
   To ask somebody
2. Rule #2
   demander qqch
   To ask for something.
   In english, we would need a for preposition. But not in french.
3. Rule #3
   demander de l'infinitif
   e.g. demander de faire le menage
4. All is well until I came upon this sentence:

   la maniere de demander de l'aide.

   I was basically confused by the 2nd de. Doesn't rule #3 states that an infinitive follows a de. A quick post to wordreference forums helped to clear my confusion.
   demander de l'aide
   Ask for some help
   
   demander l'aide de quelqu'un
   Ask for the help of somebody
   
   demander la pomme
   Ask for the (an) apple
   
   demander des pommes
   Ask for apples.