for a low and slow (LAS) cook start, load your coal. depending what you're cooking and for how long, i invert my charcoal baskets (CBs) so I don't have to fully load the coal grate.
for a brisket, i'm using 2/3 of a full load (9-10 hours easily of fuel). for pork belly im using 1/3 a load (4-5 hours fuel, easily).
i load the coals and wood (wood sandwiched in between the coal layer).
then i remove around 5 coals (briquettes are what I use for LAS, not lump charcoal), and then place 2-3 napkins with bacon grease, cooking oil, or any fat inside those napkins. and then i use a small crème brulé torch and light the greasy napkins. (napkins in the US are like a paper towels for your hands and face, not ladies products).
i start the LAS cook with the lower vent in the fire position, all the way open. once i see i have flames going, i then lid the WSC and pop open the rapid heat top vent to have maximum airflow.
after 10 minutes, you can then place the deflector in place, or you can place the deflector in place before you first close the lid. i prefer to wrap my deflector in heavy duty aluminum foil for easy clean ups when done cooking.
after 15-20 minutes, i'll then dial down my bottom damper to SMOKE setting and close the rapid heat vent and open that vent to 70% or so.
get your meat on and monitor temps for 40 minutes or so. then make fine tune adjustments.
you can see in my cook graph on my link what my grill temps were. basically i held less than 275F for the majority of the first 5 hours.
https://cloud.thermoworks.com/shared/wxTmJqX9hwZgTLfleUlY