First we have to prepare our storage devices. We assume, we only have one 10GB hard drive, which we divide into 5 partitions:
EFI System Partition - /boot/efi - 512MB
Boot Partition - /boot - 1GB
Swap Partition - 1GB
Var Partition - /var - 3GB
Root Partition - / - 3.5GB
sh# cfdisk /dev/sda
...
sh# mkfs.vfat /dev/sda1
sh# mkfs.ext4 /dev/sda2
sh# mkfs.ext4 /dev/sda4
sh# mkfs.ext4 /dev/sda5
sh# mkswap /dev/sda3
sh# mount -onoatime /dev/sda5 /mnt
sh# mkdir /mnt/var && mount -onoatime /dev/sda4 /var
sh# mkdir /mnt/boot && mount -onoatime /dev/sda2 /mnt/boot
sh# mkdir /mnt/boot/efi && mount -onoatime /dev/sda1 /mnt/boot/efi
sh# pacstrap /mnt base
sh# genfstab -U /mnt/ >> /mnt/etc/fstab
sh# arch-chroot /mnt
sh# vi /etc/timezone
Canada/Eastern
sh# ln -svf /usr/share/zoneinfo/Canada/Eastern /etc/localtime
sh# vi /etc/locale.gen
...
en_US.UTF-8 UTF-8
sh# locale-gen
sh# vi /etc/locale.conf
LANG=en_US.UTF-8
sh# vi /etc/hostname
arch-linux.some.domain
sh# passwd
...
EFI
sh# pacman -Sy grub efibootmgr
sh# grub-install --target=x86_64-efi --efi-directory=/boot/efi --bootloader-id=grub
sh# grub-mkconfig -o /boot/grub/grub.cfg
BIOS
sh# pacman -Sy grub
sh# grub-install --target=i386-pc /dev/sda
sh# grub-mkconfig -o /boot/grub/grub.cfg
sh# exit
sh# umount /mnt/{boot/efi,boot,var} /mnt
sh# reboot