Best bet is to youtube, Evans or Parktool websites loads of how to do it clips to help you do anything. Also helps if you post in workshop section and say what bike it is or what crank is fitted as lots of different ones.
As stated above there are different fixing methods.
From your brief description (I'm assuming the bolt you have undone, screwed into the BB spindle) it sounds like you'll need a crank puller. Should be able to pick one up for around a tenner and very simple to use.
Posts
Some need crank pullers, some don't.
From your brief description (I'm assuming the bolt you have undone, screwed into the BB spindle) it sounds like you'll need a crank puller. Should be able to pick one up for around a tenner and very simple to use.
Park tools web thingy will show you
Duster
My Bianchi