Personal devotions go by many names such as your "quiet time".
There is no law about it. It is just a very, very good idea and we suffer when we do not do it.
It simply means spending time with God daily. That time can involve any of the spiritual disciplines but the main ones are Bible reading, reflection and prayer. People might add listening to, or making, Christian music or journalling or...
There is no one way that suits every different personality type. The main thing is to have intimate fellowship with God in the way that works best for you. Here are some suggestions.
How To Have An Effective Quiet Time
There are 5 videos in this series
Discovery - (Scripture Union). For those new to the Bible. Available in printed form but also available free online or by email.
Encounter With God - (Scripture Union). For seasoned Bible readers. Available in printed form but also available free online or by email.
Bible In One Year - Nicky Gumbel. Available in a smartphone app or by email.
A playlist of short devotions taken from Charles Stanley's sermons.