If you're ordering coffee from the Nespresso website, just add the Recycling Collection option - it's free.

What happens is simply that, on the day you receive your order, somebody will also come and collect your bag - no need to mess with labels. If you need a bag just order it on the web - it's free with any coffee and you can get multiple ones in one go.

Otherwise, when you go buy the coffee, just bring the bag with you. Actual Nespresso shops will all accept it, popup stands might not. The last option (imho the less convenient) is to print a label then bring the bag to one of those delivery-pickup places like cornershops and petrol stations.

We recycle a bit differently, possibly because we're in the US: Nespresso sends us pre-paid UPS bags. We fill the bags with used pods, and take them by the UPS store every once in a while.