Following fashion, Mike gets computer device (5)
I believe the answer is:
modem
'computer device' is the definition.
(short for modulator-demodulator)
'following fashion mike' is the wordplay.
'following' is a charade indicator (letters next to each other).
'fashion' becomes 'mode' (synonyms).
'mike' becomes 'M' (phonetic alphabet: alpha, bravo, charlie etc.).
'mode'+'m' is 'MODEM'.
'gets' acts as a link.
(Other definitions for modem that I've seen before include "Device to connect a computer to a telephone line" , "Connection betwwen computers" , "Digital-analogue converter" , "Device used with computer" , "Computer/line connector" .)