Catch the Malpensa express train service from Piazza Cadorna or Central Station. The journey from Cadorna takes 29 minutes, whereas from Central Station it’s 52 minutes. The trains run from approximately 04:30 to 01:30, depending on which route you take, and trains depart every 30 minutes.
Linate Airport is located just 7 km (4,5 miles) from downtown Milan. You can reach it easily by public transport; buses on Urban Line 73 run every 10 minutes from 05:35 to 00:35 and cost just EUR 1,5. Alternatively, you could take a coach directly from Milan Central Station to the airport, with these departing every 30 minutes.