Hi I am from Florence SC. Usually someone hosts a RR---they send out to the first person. That person takes out what he/she wants and mails to the next person. You put in as much or more as you take out. It continues "around" til it gets back to who started and often it makes another "round". If you are looking to trade seeds often someone will say I will send you 10+ packs of seeds and you send me 10+. Let me know if you want to trade. Hope this helps--Dale

And there are some RRs that are more like Roud Ups, where everyone sends their seeds to the host and the host redistributes the seeds to the rest of the people in the group.

And then there's the ones where you join and the Host pairs you up with someone to send to and someone to send to you.

Some last just as long as it takes the goodies to go from person to person. Others can be as long as a full year's commitment.

Also, try checking out this forum's Frequently Asked Questions

Here is a link that might be useful: FAQ