is it better to use all 10 chances or spread them out in the store

Hello PartTime and Welcome to the Community!  I’m not sure I understand your question, but if you buy ten chances on an item, your odds of winning that item are better than if you bought one chance on ten items.  It shouldn’t matter whether you buy all your chances at one time or spread out over time, as the odds are the same.  Some community members use different methods on timing their buys; whatever works for you!  

I spread them out over the week.  A couple of people who won multiple times posted a couple of years ago that the drawings seem to be done at specific times which makes sense because people have won multiple times in the same week.   There has never been an official explaination of how the drawing is done though.