Begin by making little changes.
If you do this, it may help form your decision and may even spur you on to quit. It might also help you know whether you will be successful or not before you even quit. (I discovered you can make quitting like a game with/between yourself.)
How and why can this work you ask? Because seeing new symbols of quitting daily will either stir your thinking or make you turn away.
So here are a couple ideas:
Put an extra key on your key ring. Make it something that stands out so you'll be reminded of the changes to come every time you see it.
Get that key tomorrow. Stop at a key shop and have it made for your front door so you see it often or, for something else you open often. If you don't use keys, you could write something on the glass you use or a coffee mug. You can use nail polish if you don't have any access to paint.
This can be your reminder for as long as you need it.
Hang something you can't miss noticing from your rear view mirror (if you still drive as a reminder of things upcoming and your freedom.
You Can Be So Far Ahead (Before You Even Quit)
If You Change Your Thinking And Get Out Of Your Smoking Zone
Planting These Tiny Reminders Before You Quit Will Only Help.