Let's practice. You are pilot of F-ABCD. You need to spell your registration for the tower on initial call.
Your registration: F-ABCD
Spoken aloud: "Foxtrot Alfa Bravo Charlie Delta"
Notice that each letter gets its own word. There is no "and" between them. You do not say "Foxtrot and Alfa..." You simply say the words in sequence, clearly and deliberately.
The letter "X" is pronounced as "X-ray," not "eks" or "ecks-ray." Practice this a few times aloud. Yes, aloud. You will transmit this on the radio, so you must be comfortable saying it.