This really depends on the state you live in. Some are only valid for a certain amount of time. Some states also having a waiting period. Here in MA the waiting period is 3 days if you apply on a Tuesday, you can’t pick it up until Friday.
Depends on your are. Some are only good for 30 days. Jump online and just google "justice of the peace - your county" and it will bring you straight to the county page with all the details. Make sure to check the waiting period too. We live in WI but our wedding is in IL. In WI there is a 5 day waiting period and it is good for up to 60 days after you get it. You can also get married in any county. In IL, there is only a 24 hour waiting period, its good for 60 days, but you have to get married in the county you got the license in. Good luck!
Really whenever you're able to go within the required time frame. We're not getting our license until the 29th for our August 10th wedding. It'll be valid for 60 days with a 24hr holding period so we're good to go
Go by your state law where your wedding is being held. I live in Kentucky but we are getting married in Savannah Ga. luckily for us Georgia has no waiting period and there’s no expiration for the license. So we actually got out marriage license back in the end of June and our wedding isn’t until November.