بسم الله الرحمن الرحيم
(1) You should write complete name i.e. Muhammad Aarif.
(2) Aarif means: one who recognizes, and in Islamic terminology it means one who has got the cognizance of Allah and acts upon Shariah in all matters and had high morals.
(3) You can take ‘Hassan’ as your title.
Allah knows Best!
Darul Uloom Deoband