When looking to naturally shine your houseplant leaves it is best to always start by cleaning the leaves with a damp cloth (or Southside Plant's very own houseplant dust wipes). When doing so you should be sure to support each leaf by placing one hand gently underneath and wipe down the top of the leaf with your other hand, moving away from the stem. Then repeat on the underside of the leaf. Take note that the underside of the leaf is where common houseplant pests usually like to hide.
Another option is to give your plants a shower! Yes, a shower. Much like the ones we humans take. To do this, place your plants in planters with drainage holes. Then bring them to the shower and sit them down. With gentle, lukewarm water, carefully run your hands through the foliage to ensure that the water washes the leaves’ undersides. This method especially works well for moisture-loving ferns, orchids, and palms. Just be wary that you don’t overwater your plant in the process. Instead of handing your houseplants a towel to dry off with, gently shake excess water off the leaves after their shower.
However, if you want to look into your plants' health a bit more, please take a look at this article on fixing droopy leaves.