hi jan and welcome.
when you see a post you want to reply to, you can either hit the

button and it will copy that exact post. it also "quotes' the post in your post.
you can also just hit the

button located at the top left. this brings up the reply box. or you can use the Quick Reply box located at the bottom of each thread. the Quick Reply only has so much room, so if you are planning a long reply, i suggest the Post Reply button.
here is a link to the PN forum here:
http://neurotalk.psychcentral.com/fo...aysprune=&f=20
to start your own thread just click on the

.
Chemar has created a wonderful thread to help new members also. here is that link:
http://neurotalk.psychcentral.com/sh...ad.php?t=18185