Well to create a partition, you will need to erase a hard drive, due to formating this these partition, which I'm sure aware of considering you done this on a PC.
Since you are using Jaguar, you will have to do this in Disc Copy. Select the volume, go to Partition (anyone correct me if I'm wrong, i think Jaguar had this selection like Panther). Then specify the number of partitions, select the sizes for these partitions and thats it. I wiped my drive clean before i this this formatting.
As for the Applications, I dragged them over from my X partition to this other partition. I will say it is better to install them onto the X partition, then transfer them this way. And this has worked for me without any problems, and i did this after i had system problems that forced me to wipe my X partition, so maybe a year and a half ago.