This game, Grimworld, is an asynchronous multiplayer survival game, where contribution of every player (or lack of it) defines whether every other person survives. Thus, the most important point of this little guide, is that
I know too well how it is when you are trying to build some defences and almost noone else is helping, and then hordes of monsters come at the night and rape make bad things to you and everyone else, and they do it hard, making no distinction based on how much every separate villager worked, believe me on that one. Your job is to get as many people as possible working together and in one direction. If you won't help them organize, noone will.

There is no place for selfishness or any kind of personal belongings in the circumstances in which your character is found in the game. If you don't give all you have - your strength, wealth, wits and all your stamina to the last drop of sweat - to the community, you will die (and every other villager, too).

(at least for a while)

1. If you aren't going to log in the next day, do not even start the game! You'll ruin it for everyone else - afk persons take up limited village space and there is no easy way to get rid of them (and so far no way to get fresh people instead, at all). If you started playing, do your best to try sticking around for a couple of days, since it doesn't take a lot of time every day to at least donate all your SP to digging the moat or something (it actually takes less than a minute to do so).
2. Don't just take items out of storage! Take the tools you need, use them, put them back as soon as possible. Without most of the tools, even crafting is impossible. There is rarely a need to keep stuff in your inventory at all - just make it a habit to dump it all into the storage as soon as you get to the village. HOWEVER, you'd better hide the most valuable items in your home for the attack - in case it is more powerful than your defenses - just don't forget to put it back to the common storage as soon as the new day begins.
3. Do not eat food when you are overfed! Especially if you weren't the one that brought it to the village. You'll just waste resources.
4. Scout every day! It costs only 3 SP and helps to locate monster lairs.
5. Use all of your SP every day - you waste it when it reaches the limit.
6. READ chat.
7. READ ingame forum discussions, and participate in them. Be creative. Make suggestions for defense strategy, village rules, etc. It helps.
8. Always know what the village needs and what is the current defense building project, and do your best to participate and encourage other villagers to help, or else YOU ALL ARE GOING TO DIE A HORRIBLE DEATH. Also don't forget to guard the village, if your character is in a position to do so (go to Your Home - Night Attack Actions (shield-moon button on the left) - Guard - Confirm). If you are wounded and/or have bad mental state, you'd better rest. However, if there is not enough defenders, you'll very likely die anyway, so in such a case it is better to guard even if you are in bad shape, in my opinion.
9. Check who is being voted up to be banished and actually cast your vote. You can reasonably banish afk people from day 3 morning, or even last couple of hours of day 2. You can propose only one person per day to be banished, so encourage other players to do it dailty, too. There are a lot of stuff in afkers' inventories that you actually need to survive. You can also banish people who only waste resources/steal items and provide zero utility to the community, but make sure to clearly communicate that to villagers.
10. Know what you are doing. Don't wander off without sufficient food, start starving and lose the ability to return and then cry for help in chat. Don't gather wood 10 tiles away from the village when there is a forest right next to the it. On the other hand, if another person is in trouble, you should try to help them, unless it is unreasonably dangerous or would waste too much resources.
11. Watch the ingame tutorials. They are short, and really helpful.
12. Don't be a ♥♥♥♥! Communicate with other players, you need to work together to survive.