Spider Webs and Cob Webs are used in the practice of Hoodoo/Rootwork, as well as other magical traditions, in binding spells to magically tie-up or incapacitate someone and prevent them from doing harm, in domination spells, in love spells to trap a specific person, and are used as an ingredient in enemy work or revenge spells.
Most practitioners who use webbing in their work recommend the web of orb-weaver spiders, the type of spiders who create the large, beautiful webs that are most often associated with Halloween decorations. Personally, I do not use these as I have a fondness for orb-weaver spiders. Instead, I would recommend cob webs, especially cob webs that include small dead bugs that became trapped in them to symbolically reinforce the trapping of one's enemies.
How To Collect Cob Webs
The easiest method of collecting cobwebs is to use a q-tip. Swirl an end of the q-tip around in the cob webs until one collects a good portion. Next, either cut off the tip or else pull off the cotton head of the q-tip. Add this to a bottle of any binding-type condition oil, tear it up into small pieces for inclusion in incense and powders, or add it to a doll-baby.