I'm not a great example to you, Kez, cause my DD hated tummy time too, and she's a late crawler. But when we did tummy time I'd prop her in front of a mirror (she just loves herself, bless her) and that bought me another minute or two.
The rolled-up towel is still productive in the early days: their arms are out in front of the towel, so they can still push themselves up, and they still have to hold their head up.