I know you all know what a seeder and leacher is but for this quick guide i'll change the leacher definition , and some of you may already know this stuff by using logic but some don't so please:
seeder: one who has the complete torrent file (100%)
leacher: one who is downloading the file he/she maybe uploading but its still a leacher(less than 100%)
LEACHERS:
1. Read my previous post about speeding bitcomet.
2. Set only one torrent file to download, if you have a high connection you can put 3-5, but leaving only one to be downloading, maximizes your download capability.
3. Download speed is PROPORTIONAL to upload speed (meaning if one goes up the other goes up as well) , so if your downloading a torrent, don't try to seed another torrent at the same time. Because this will cause your download speed to go down, and thus also causing your upload speed to go down. If your a high connection user you can do it, if not, stick to 1 task only.
SEEDERS
1. Change your MAX upload rate to unlimited. ***This is if you only plan on seeding some torrents and leaving your computer on.
2. If you plan on surfing the net while you upload change it to an 80% of your MAX allowed upload rate ( http://www.speedtest.net/ ). I had this problem occur. I put my MAX upload rate to unlimited (with my univ. connection) and when it reached 983KB/s. Bitcomet would not open and when it finally did it was so slow at doing everything.
3.You can put more than one task to be seeding (I mostly seed 3 torrent tasks at a time), keeping in mind the leachers that are connected. (Happened to me that I left a seeding task on but there where very few leachers to seed to, was only seeding 10kB/s when my max is around 80kB/s)
4. Sometimes do a little math (just a little) if you normally upload up to 100kB/s and your seeding 5 torrents. And you add up there total upload you get 80kB/s this means you can seed another torrent so you can reach the 100kB/s upload.
And that's all from my experience as a seeder if you have something else, just share it with us!