Be led by the Spirit in how you choose to fast.
Some of us will skip lunch for a week, and use that time for prayer or worship.
Some of us will choose intermittent fasting.
Others may do the Daniel Fast.
Still others may fast television or social media.
The main thing to keep in mind is that you are led by the Spirit. However you choose to fast, keep in mind that fasting should hurt: not physically, but you should feel as though you are losing something. If you're fasting something that is easy to give up, you may not truly be fasting.
One should also notice the importance of replacing what you are fasting with time spent with God. If you fast food, but you don't pursue Him, you're not fasting. It's just a diet.