Thoroughly rinse vegetables (don't scrub), and pat dry with a clean towel.
Slice off of carrot tops, and chop into lengths to fit your mason jar lengthwise, allowing for few centimetres of headspace.
Chop daikon to the same length as the carrot.
Slice carrot and daikon into sticks to your desired thickness.
Peel the garlic and keep whole. Slice ginger into thin strips (peeling is optional).
Pour mustard seeds into the bottom of your jar and pack down with basil leaves. Start to add in your vegetable sticks as tightly as possible, tucking garlic and ginger in as you go along. It may help to turn the jar sideways after a while to fit more in.