For exemple: You are from Mexico and wants GF Sri Lanka
1 ) You go to where its written Sri Lanka and post the GF you offer (or say you can send blank copies) and how to contact you:

GF Mexico
email: / facebook / instagram/ postcrossing profile

2) In this example, if you are from Sri Lanka and you want to receive two blank copies, you can write it in the  Sri Lanka page (you can also say what you are looking for) :

I can send W&S GF Sri Lanka if you send me two blank copies
email: / facebook / instagram/ postcrossing profile

3) When someone from Sri Lanka sees your post and wants GF Mexico, he/she will contact you and answer your post.
4) You should erase your post once you get the GF Sri Lanka!
5) Vote on the questions at the right side of the page to leave a feedback

Ps: You can offer different things with the links but its better if you only post GF because the goal is to complete everybody's collection.
Ps2: You can post in more than one country
Ps3: Dont answer others in other countries. For exemple: You are from Serbia and needs GF Mexico. You should go to Mexico and write Serbia and wait. You are not allowed to answer the post of GF Mexico in the Sri Lanka space. Lets keep it with order. This was created to help everybody.!

If you collect FOTW:
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All right of pictures to Ewa Słocińska who designed this collection
You can buy these cards at her website: