Suspend and hibernate

Kernel
Make sure the following variables are set to 'yes': SUSPEND HIBERNATION

Available suspend modes
To see available suspend modes use

Suspend to RAM
Preferred commands to suspend are

or

A more raw method is to

Suspend to disk
for suspend to disk make sure you have a swap partition or swap file

Can not resume after suspend
In case resuming from suspend does not work, disable the security chip in BIOS/UEFI and try again.

Related links
https://wiki.gentoo.org/wiki/Power_management/HOWTO