How do I stop dozing off during meditation!?

[GroovyGuru]

Picking up the habit again, I want to take it very serious (relative to how serious I was taking it in recent times). 30 min morning, 30 min evening. I have been doing it all week and have seen through all the sessions but I have serious problems of drifting into sleep when I meditate. 
 

A year or 2 ago I used to meditate more seriously and I don’t remember this being an issue. It’s like I catch myself falling asleep, and I tell myself: “that’s it! Focus now. Breathe in, breathe out, breathe in, breathe out.” Next thing you know I have all these random images in my mind and my head is slowly sagging down as I fall asleep! It’s so frustrating because I want these sessions to be productive. 

Are there any practical tips or is it a matter of just sticking through it every single day and gradually getting better?

[sleep]

You can try meditating standing up or with your eyes open.