This is my usual go-to first aid when my baby’s tummy aches. But I have no idea what’s the other easy way if I ran out of the same?

I used Ruyi Oil for my kids too whenever they tummyache. It always effective to relief tummy pain. To add on to Samantha's comment, there are two types of ruyi oil (refer to the picture attached). The one on the left (with Mandarin Orange) is suitable for babies as it is less 'hot' compared to the right one. I used Telon Oil to do tummy massage twice a day after bath for baby, as it is very mild to baby, at the same time to relief windy tummy. You can refer to this website on how to carry out tummy massage. http://sg.theasianparent.com/how-to-massage-your-baby-to-relieve-gas-and-reflux/?utm_content=buffer7571f&utm_medium=social&utm_source=facebook.com&utm_campaign=buffer