An easy way to do a vacuum filtration without the right apparatus is to use a bottle, on wich you place as usual your funnel and your filter. You must make a hole in the top of the bottle, and you use a simple cleaner aspirator placed on this hole to make the vacuum. Beware, the liquid must drip really down the hole if you don't want to see it enter in the aspirator. You can prolung the end of the funnel with a pipe to avoid that. Tests must be done with each home-made apparatus. I have tested it and it works.