Printing shipping label without postage on it

[nananner]

So you got a very small package needing to be mailed, small enough to use stamps, but too large for a ordinary envelope, is there a way to print a shipping label without purchasing postage online?

i really hope I explained that clear enough T_____T

[Quandary]

I believe at one time (a long time ago) you could do via USPS however, that's not an option anymore.

[nananner]

What about the packing slip?