Great topic and I love the Veteran's responses!
Obviously no direct experience with me, but my grandfather talked about it a couple times in his letters home while he was in boot camp. In the first instance, he is writing home after being in boot camp for about a month and says:
“I got $29.53. They took two months insurance out (that was $14.00), they took $1.50 out for laundry. The laundry is taken out every month and we can send in all the clothes we want and al it costs is $1.50 per month so thats not bad is it?”
The next mention is six months into his training and just a day before they leave for the Louisiana Maneuvers. At this point he is a Corporal and is acting as Weapons Sergeant (which he ultimately becomes and serves as during the war). He says:
“I will try to write you again tomorrow if I can, I may have to guard the payroll. You see we get paid tomorrow and guarding the payroll is one of the Weapons Sergeant jobs and as I am acting as Weapons Sergeant I may have to do it.”
In looking at the dates of those two letters it looks like payday was at or very near the end of the month (or possibly more and these just happened to be written then). I do not recall any more of him referencing the pay except how much more he would get if he made the next pay grades.
In my conversations with a veteran friend, he remembers waiting to get paid and then having to go up to the desk where the money was and having to say his name, rank, serial number, etc. all while the the money is being guarded by a large man with a side arm!