"We must take change by the hand or rest assuredly, change will take us by the throat." Churchill
We recommend that you meditate every day if possible, at least on weekdays. Sometimes, your weekend schedule may disrupt your normal routine.
The important thing is to continue to progress regularly.
If you take a few days' break, don't worry. Take advantage of this to observe with clarity the thoughts or emotions that have stopped you. Review the deeper motivation that led you to meditate – and still does.
If you sit and begin meditating, after 10 or 15 minutes you will begin to slow down, to turn your attention towards yourself, enabling you to acquire the skills you need to calm and guide the light of your attention. You can also take short meditative breaks of three to seven minutes from time to time during your day to ensure that you remain in contact with this state of calmness and clarity. Finally, after a few months, sessions of 20 to 30 minutes will probably be more appropriate for your requirements.
But remember that the important aspect is the quality of your attention rather than the duration of the meditation.