I think the most "friendly" way would be using jumpdrive as you said and running gparted.
There should be two partitions for the blockdevice which is exposed over USB.
The first partition (about 115MB in size) is the boot partition. You want to resize the second partition which holds the root filesystem.
Btw: If I'm not mistaken the newer images do resize the filesystem on the first boot, so you could just flash it anew (remember to backup your /home if you have files in there that you do not want to lose)
Also: Feel free to ask for help here or come have a chat in the matrix channel. You can definitely find people there willing to help ;)
There should be two partitions for the blockdevice which is exposed over USB.
The first partition (about 115MB in size) is the boot partition. You want to resize the second partition which holds the root filesystem.
Btw: If I'm not mistaken the newer images do resize the filesystem on the first boot, so you could just flash it anew (remember to backup your /home if you have files in there that you do not want to lose)
Also: Feel free to ask for help here or come have a chat in the matrix channel. You can definitely find people there willing to help ;)