open a terminal and type slackpkg help this will show the types of instruction you need.
but if you want to download them only it is this command. slackpkg download "program"
don't for get to do a slackpkg update to get the news programs on the mirror. the
slackpkg download "program" it will be placed in the./var/cache/packages "your slackware".
mine is /var/cache/packages/slackware64 there you will see the mirrior of slackware.
After you saved a bunch you can install or fined the like this
if all else fails got to slackware click packages then search or browse for your package and save it. then navigate to the saved package and type as root upgradepkg "your package.
if you get no package to upgrade then you just need to install it. installpkg.
Now lets say you have a bunch of new programs you want to install not upgrade. in a certain directory. cd to the directory and type as root pkgtool and install from current directory.
Slackware is very visible no smoke and mirrors.
Nice thing about people that use slack we take time with other slacker.
I could have said type man slackpkg man pkgtool and everything I type was there.
Have a deluxe day.