So It's really easy and simple you just need to go this location down Below and pick as many as mushrooms and flowers you can.

So Empty Up your whole inventory as much as you can and go to this place between 22 - 07.
The Reason why i recommend you to farm around this time is because during night time you can find more Cep and also there will be less players telling you stop taking their mushrooms.

In This Screenshot you can see how much tokens you can make from selling Milk Mushrooms And Cep.
I Highly Recommend to sell these 2 type of mushrooms to the Barman , you can get way more money from doing this and also you will get Experience points as you can see.

Most Players don't care about these 2.
but since you are collecting Milk Mushrooms and Cep you better collect these Two along side with others.
You can make 1 token/1 Experience point per each Flower and Amanita.
And again i highly recommend selling these 2 to the Doc.
.

If You Are Level 7 or Higher Than That try purchasing the Gorka set.
The Reason why is suggest doing this is because you won't get any damage from the annoying rats near the mushroom area there is not a lot of them in that area but sometimes you may need to deal with them.
Once you purchase the set, store all of your guns and ammo and basically everything you have and only keep your knife so you will have more inventory space and will be able to carry more.
After Each Farm Run Make Sure You Repair your Knife , your Jacket , your Pants And your Boots Do not forget to do this because if they break you won't be able to sell or repair them.

You will need to deal with the rats when you are over there but i don't recommend grabbing everything from their corpses but if they drop Rat Eyes grab them cause you can sell them for a pretty good price to Rafik.

If You like Achievement hunting this is the easiest way to get the Mushroomer Achievement.
You just need to collect 500 mushrooms.