how to stop sanity from going down?

[Someasianguy]

could never figure this out

[baldoleo]

picking up flowers, making a new recipe for the first time, equipping a sanity-boosting hat/vest, standing near a befriended pig (usually easy at night), standing near glommer, eating crock pot recipes, eating specific sanity boosting recipes ( taffy comes to mind ) and most importantly eating cooked green mushrooms. use the wiki for more information

[WarWise]

What mkez said. That helps you raise your sanity.
You cant stop it from falling, it will always happen in the nights and if you are wet. Being damaged lowers it, and standing next to corrupted things like flowers also.

Near the start the easiest way to raise it is by picking flowers (5 points each) and also that hat with flowers, which takes 12 to make. Using an umbrella also raises it a bit.

[J20Hawkz]

Everything that has been said above is excellent advice. What I do however is try and find at least 1 pig, feed it one piece of meet thereby befriending it and then all do is hit a tree with your axe once and watch the pig start chopping away while you stand next to it and get a nice big fat sanity boost.

[El Presidente]

Yeah flowers are pretty good in the start - I especially like starting up flower farms with bee hives. After a while I have too many flowers and my sanity can stay maxed for days :)

[Llinara]

I think that there's a sleep roll that makes you sleep and acording to the description it raises the sanity. Never try it tho

[Cheese n' Beans]

Sleeping in a tent is a great way to restore a whole heap of health and sanity at the cost of hunger. In the long run, a Tam o' Shanter (which has a 25% chance to drop from MacTusk when killed) is ideal, as it has the highest sanity regen of any clothing item in the game (6.7/minute), completely negating the -5/minute sanity drain you get from dusk and night alone. A top hat is always useful earlier on, only taking 6 silk to craft and giving you 3.3 sanity/minute, which should be enough to stop you going insane if used whenever needed. During dusk/night, you can equip a dapper vest - which gives an additional 3.3 sanity/minute - as well as the top hat to negate the sanity drain during this time of day, which helps to stop yourself going insane and reduces the need for other sanity-boosting items, such as: taffy, cooked green caps, pumpkin cookies, sleeping, and various crockpot recipes.
Early game, just pick flowers whenever you need to.

[No Leaf Clover]

Play as a character whose sanity is easier to manage, for a start. Wolfgang is hard to manage while I find Wendy is easier in that regard.

[Vulrhund]

Wear a garland :3

[NecroMaster]

Playing as WIllow, Wendy or Maxwell are good for sanity.
Willow will gain sanity around fires, Wendy will not lose sanity in darkness and Maxwell constantly gains Sanity over time.