Depends on how long your period is. It may be helpful to have a super short form, memorize it, because if it is memorized it is much easier to get through it. This is why in Buddhist chanting they have set things and then they just chant it, they don't take 20 minutes to get through it. So by actually writing a sentence down and than putting it to memory, it is much easier to remember and easier to recite to ourselves. In that way, then if we wish to expand it, it will be more helpful. But in this retreat it's not a problem that it is 20 or 30 minutes because the morning sit is longer than that, and if there is a tendency in the morning to be kind of dreamy or sleepy, well at least you are putting forth the energy to meditate. However it may be very helpful to put that short form to memory so you can get through the period.