As both a student and a teacher of Mediation i know how valuable it is to have somebody hold the space for you. One of the key aspects of holding space is having somebody else watch the clock and gently alert you when time is up. When you practice at home this is more difficult but modern technolgy can help.
The Practice Timer app is a free gift from Stillness Therapy and is given with the wish it will be of benefit to you.You can find it in the google play store
A simple practice timer App that plays a pleasant sound when the time is up. It is also supports interval times when a short bell will be played.
Use for your meditation, yoga or any other practice. Let this hold the space and keep track of time so you can loose yourself in your practice.