You’ll find the best before date of your kit located on the tamper sticker sealing the base of the silver box.
Store somewhere cool and dark like a pantry. If your house is super hot in summer then it is possible the heat will have some effects on our products - the worst that could happen is things like chocolate might melt or the matcha might become a bit discolored, which doesn’t affect the taste of the cake. This is unavoidable with high quality ingredients and no preservatives added. If you are worried, you can store the kits in the fridge, or you could just bake your cake ASAP after receiving it.