[galaxy-user] wiggle file

Hi, this should be simple but it is not..forgive the newbie question. i am doing chip-seq. bowtie>sam filter for mapped reads>MACS. i want to create a wiggle file that displays in ucsc, but when i choose the "WIG" option on macs, and then try to show it in UCSC, it treats each line of the created WIG file as a separate track, and obviously does not show it as a graph. is there a wiki page somewhere that can give me the basics? or can someone point me in the right direction? thanks. rich