lsblk

partition:
gdisk /dev/sda
o (yes)

n (Add a new partition)
Partition number 1
First sector 2048
Last sector 1050623
Hex code EF00
n (Add a new partition)
Partition number 2
First sector 1050624
Last sector 2099199
Hex code 8300
n (Add a new partition)
Partition number 3
First sector 2099200
Last sector (press Enter to use remaining disk)
Hex code 8E00

w (write)

open crypto:
cryptsetup luksOpen --allow-discards /dev/sda3 lvm

setup lvm:
pvcreate /dev/mapper/lvm
vgcreate vg /dev/mapper/lvm

create swap & btrfs (root)
lvcreate -L 2G vg -n swap
lvcreate -l +100%FREE vg -n root

format:
mkfs.vfat -F32 /dev/sda1
mkfs.ext4 /dev/sda2
mkfs.btrfs -L btrfs /dev/mapper/vg-root
mkswap /dev/mapper/vg-swap
swapon /dev/mapper/vg-swap

create btrfs-subvolumes:
mount /dev/mapper/vg-root /mnt && cd /mnt
btrfs subvolume create @
btrfs subvolume create @home
btrfs subvolume create @log

unmount & mount:
cd && umount /mnt

mount /dev/mapper/vg-root /mnt -o subvol=@,discard,ssd,compress=lzo,autodefrag
mkdir -p /mnt/{boot,home,var/log}
mount /dev/sda2 /mnt/boot
mkdir /mnt/boot/efi
mount /dev/sda1 /mnt/boot/efi
mount /dev/mapper/vg-root /mnt/var/log -o subvol=@log,discard,ssd,compress=lzo,autodefrag
mount /dev/mapper/vg-root /mnt/home -o subvol=@home,discard,ssd,compress=lzo,autodefrag

install:
pacstrap /mnt base base-devel btrfs-progs vim grub efibootmgr sudo bash-completion

generate fstab:
genfstab -p /mnt > /mnt/etc/fstab
Change defaults to defaults,discard for swap partition entry in fstab if you have a SSD

chroot to arch:
arch-chroot /mnt /bin/bash
echo computer_name > /etc/hostname
ln -sf /usr/share/zoneinfo/Europe/Amsterdam /etc/localtime (See available timezones with ls /usr/share/zoneinfo)
vim /etc/locale.conf LANG=en_US.UTF-8 LANGUAGE=en_US:en_GB:en
vim /etc/locale.gen (uncomment en_GB.UTF-8 and nl_nl.UTF-8, or other locales that you want)
locale-gen
echo LANG=en_GB.UTF-8 > /etc/locale.conf
echo KEYMAP=sv-latin1 > /etc/vconsole.conf
passwd

create keyfile for luks partition:
dd bs=512 count=8 if=/dev/urandom of=/crypto_keyfile.bin
cryptsetup luksAddKey /dev/sda3 /crypto_keyfile.bin
chmod 000 /crypto_keyfile.bin

edit grub:
GRUB_CMDLINE_LINUX="cryptdevice=/dev/sda3:lvm:allow-discards root=/dev/mapper/vg-root rootflags=subvol=root resume=/dev/mapper/vg-swap
GRUB_ENABLE_CRYPTODISK=y

edit /etc/mkinitcpio.conf:
MODULES="crc32c-intel"
HOOKS="base udev autodetect modconf block encrypt lvm2 btrfs resume filesystems keyboard fsck"
FILES="/crypto_keyfile.bin"

generate grub:
mkinitcpio -p linux
grub-install /dev/sda
grub-mkconfig -o /boot/grub/grub.cfg

reboot:
exit
umount -R /mnt
reboot