Nice vid on the Ground Crew commo, kylania.
If you land the jet after a good run and need to rearm, contact the Ground Crew like in kylania's video, then you have to get the new loadout into the CDU.
Press and HOLD the DSMS button. HOLD it until you get a new menu that gives new function choices to select. Choose the Load function and press the DSMS again and it should switch to Load. Then you should see a DSMS Load choice on the left side - OSB 18 or 19 ? Press that to get the new loadout into the CDU.
Then press and HOLD the Load button and go through the switching process to reset that button back to DSMS. You should then see your new loadout on the DSMS page on the MFCD.
Wrecking Crew

I wish I knew how to do videos. I'd love to splice some clips together with music. Such a n00b.. when it comes to hard stuff.