Stardew Valley

Villagers will post notices on the bulletin board outside of Pierre's store in town. If someone wants help with something there will be a visible yellow exclamation point (!) there.

The quests range from gathering supplies (some need to be collected after the quest was accepted), killing monsters to catching a specific fish.
Once accepted you have typically 2 days to hand it in (it will say in the quest details, press and click on the quest in question).

Items requested by villagers this way will usually bring in a lot more then they normaly sell for.

After successfully completing 40 of these you will unlock the achievement.

There is another achievement for completing 10 requests:


Note: There are reports that the Help Wanted quests stop regenerating in the later years of gameplay, so you might want to complete as many as you can in the first couple of years.

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Writing guides/solutions is about helping the community, a lot of time can go into writing some. Thats why i wish that if you dont find the guide helpful you will leave a comment and tell the author what you dont think is correct or what might be missing so we have a chance to improve it for the next person who reads it. This way you help the community as well. Thanks!

EDIT: Thanks to CQOzymandias for letting me know that this method has been patched and will no longer work after the V1.3 update.

There is an easter egg "cheat" that is mentioned in some other achievement solutions that can be re-purposed for this.

Every item in the game is linked to a specific item ID #. Anytime that name is referenced by a character in game (whether it is your name, your baby's name, or an animal name), you automatically get those items. In this case, you can use this to your advantage to complete any Help Wanted quest you obtain.

Spreadsheet with Item IDs: https://docs.google.com/spreadsheets/u/1/d/1pDWJ_ecANNex2CBG...

The potential limiting factor to this method would be money and progress. You need to have purchased either a coop or a barn in order to house animals and then have enough money to purchase a new animal anytime you need items you don't have. I've outlined the steps I followed below:

1. Obtain Help Wanted quest from board.
2. Head to Marnie's House [Top right area of the forest].
3. Look up the Item ID(s) of what you need for the quest. In this example I need a Fire Quartz (ID:82)
4. Speak to Marnie and purchase a chicken (or whatever animal suits your fancy) and make the name [Item ID#] (my example would be a chicken named [82]).
5. Upon completion of the purchase, Marnie will send the animal to your farm and say it's name, giving you the item(s) you needed.
6. Proceed to the person who needed the item and give it to them.
7. Rinse and repeat as many times as necessary.

If you need multiple items, you can string together multiple item IDs in the name.
i.e. [82][94][123]

The new 'Special Orders' board added in 1.5 also count as 'Help Wanted' quests.

These quests seem to be seasonal, so they shouldn't be too hard to complete. You will always have a choice of 2 quests to complete, and you will have between 5-14 days to finish them.

While it would take an age to do 40 quests using the Special Orders board alone, it is a GREAT way to rack up some extra quests if nothing is appearing on the main bulletin board.

To expand on Zorsnil's solution, you can expect this achievement to take around 2 in-game years, assuming you check the Help Wanted board daily.

At first, some of the Help Wanted requests are not feasible because it's not the right season (deliver a certain fruit or fish) or because you haven't made it far enough in the game (not far enough down in mines, etc). It can be frustrating to see so many requests and not be able to do them. Don't worry, it gets easier.

Throughout year 1, even if you need the money, save at least one of each item (one carp, one sardine, one blackberry, one topaz, etc) and throw it in a chest. In year 2 you will start to get requests for items you already have, which will make it so much easier.

In addition, completing a request increases friendship points, so you can use this achievement towards getting the 5 heart and 10 heart achievements as well. However, accepting a request and not doing it can hurt your friendship points. So only accept Help Wanteds if you think you can actually complete it on time OR if you already have the friendship achievements.