Make sure its been washed down with fresh water and allowed to fully dry then before you roll it up and into the bag dust it all over lightly with talc or french chalk,
best way i find is if you have the space is to keep it inflated or suspend it from say the rafters of a garage over winter ,
but if it is rolled up in any way as was said earlier watch out for rodents, mice /rats,i stored an old Dclass rolled up at the bottom of my garden and found out that squirrells had been living in the folds over winter lucky they had not made or gnawed any holes ,,just left loads of shit.
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