Take the tops off the strawberries and halve them. Slice the half banana. Add these to the blender and blend them. Add the apple juice and blend a little more.
Alternatively, buy loads of strawberries and bananas, chop them up and freeze them according to the portions mentioned above in freezer or sandwich bags. When you blend the frozen portions, you’ll need to let them defrost a little while, and you should blend them with the apple juice from the beginning.