You can do the traditional standing calf raise machine or use a Smith machine. The goal here is to chase some progressive overload, so make sure you're tracking your sets, reps, and loading each week.
Also use an intensity technique called rest/pause. If you've never done rest/pause then get ready for some pain and gains.
After your warm-up sets, do an all-out set with a weight that causes you to fail at around 12-15 reps. Rest 20 seconds and go back at it for maximum reps. Rest 20 seconds and repeat that process one more time.