All what do you need:

sudo pacman -S niri waybar fuzzel kitty swaync fastfetch nwg-look qt6ct sddm swaybg ttf-jetbrains-mono-nerd wl-clipboard grim slurp polkit-gnome cliphist pavucontrol wlogout (or install via aur)

export QT_QPA_PLATFORMTHEME=qt5ct to file ~/.profile

sudo nano /etc/environment -> QT_QPA_PLATFORMTHEME=qt5ct

Kitty theme - Vaughn

gtk-theme: breeze-dark layan-theme

cursors: Moga-Candy Qogir-cursors (or install via aur)

Key-bind: alt + z = terminal win + s = floating mode win + v = cliphistory win + d = fuzzel

e.t.c look in Niri config

(You will need to configure the monitor yourself, as I have a slightly unusual configuration. )