Update on my trip. Arrived at around 2:30pm in HKIA, bought the ferry ticket to Macau in HKIA arrival area for 3:15 departure.

I also bought prepaid sim card at the arrival area; they got many options but I picked the 3 prepaid 3G data for HKD $298.

Went to the boarding area, right behind the place to buy the ticket, went downstairs , took the train to the SkyPier. They'll ask you if you have any checked baggage or just carry on and it'll indicate as such in the ticket.

Arrived in Macau at around 4:15pm and went upstairs in 2nd floor for the locker / storage. You'll need $25 in Macau $5 coins for 2 hours, there is a coin changer machine opposite of the locker. It took me a while to get the coin changes, for some reason it does not like my $20 HKD paper bill but it works w/ $10 HKD bill. There is a money exchange in 2nd floor, where the rates are better than the HKIA.

Took taxi to city center, cost about $20-$25 HKD. Walk around for 3 hours and back to the ferry terminal by taxi for 8:15pm departure. Bought the ticket in the ferry terminal, you'll need your passport and confirmed ticket for the HKIA destination. The ferry was late in arriving at HKIA by 9:30pm, so don't try to cut it too close.