My favourite way to help younger children blow bubbles is using a bottle (recyclable plastic or other) with an old stocking around the end. Place the stocking end in the bubble mix and blow. It will create a snake of bubbles even the youngest of children can enjoy with adult supervision and encouragement.
You can also make your own bubble blowers using the Edx Education GeoStix®– see the picture below, we have made a square, a circle and a triangle bubble blower. Alternatively you can use pipe cleaners, bottles, coat hangers and many other common household items.