Rodrigues, Vailancio, et al. “45 Beautiful Examples of Motion Blur Photography.” Smashing Magazine, 24 Aug. 2008, www.smashingmagazine.com/2008/08/45-beautiful-motion-blur-photos/.
Some techniques to not have too much light when shooting long shutter speeds it to have a high f-stop and to adjust the iso so the image quality is still good with not too little or too much light. You can also try to use a neutral density filter.