Q 2: Allah (Exalted be He) says (what means):
And (all) the Most Beautiful Names belong to Allâh, so call on Him by them
the proper way of making a Du‘a’ (supplication)?
Should I single out one Name and supplicate to Allah by means of it to ask Him to do such-and-such for me or is there another way?
(Part No. 24; Page No. 254)
The way of supplicating to Allah (Glorified and Exalted be He) with His Names, is that you call upon Him with one or more of His Most Beautiful Names, that are authentically reported. So you can say: “O Rahman (The Most Merciful)! Have mercy on me,” or “O Ghaffaar (The Oft-Forgiving)! Forgive me,” and so on.