Tap and hold on any unoccupied icon space on any home screen. A wiggling folder icon is created in that spot, with the name "new folder". As the folder wiggles, the name "folder" blinks. Tap once on the blinking name, a keyboard pops up, type a new name, tap "done" on the keyboard; keyboard disappears, the folder name stops blinking, the folder icon stops wiggling. A new folder is created.
To move it, tap and hold as usual.
To move icons into the folder, tap and hold any icon until all icons wiggle, grab the icon you want, drag it over the folder. The folder icon gets bigger and the icon you have grabbed gets a green plus sign badge. Let go, icon drops into the folder. Repeat as needed. Tap home to stop all wiggling as usual.
Tap on a folder once to open it, like opening any app. A new home screen zooms/morphs into place, with all the icons that are in the folder. To get back to the main home screen, hit home button as usual.
Rename a folder. Tap and hold a folder until it wiggles then hold a bit longer until the name starts blinking. Tap the name once, kb pops up, type new name, tap done.