Struggling with patience when disciplining my kids

I want to be the kind of dad who leads with love and shows Christ's patience, but man some days my kids test me and I feel myself getting angry instead of staying calm. This morning my 5 year old spilled juice all over the kitchen right after I told him to be careful and I raised my voice way too much. I felt terrible and apologized to him but I hate that I react that way. How do you guys keep your cool and actually model what we're trying to teach them about self control and grace? Trying to pray through this more but looking for real dad perspective.