Many of our houseplants come from tropical climates, so they're used to higher levels of humidity than those found in most homes. There are a few ways easy ways to deal with this and make them feel at home.
The first option is to put your plant in a humid room, like the kitchen or bathroom. Another option is to regularly mist your plants - that means spraying them with a fine mist - which will imitate their natural humid environment. It's really simple and just takes a few seconds.
Grouping your plants together can create a humid microclimate, as they release moisture through the transpiration process. You could also try the clever trick of filling a tray with pebbles and half-filling the tray with water. Place your plant on top of the pebbles, making sure it's not actually sitting in the water. This increase in moisture can really help your tropical plants to flourish. Make sure to replace the water from time to time so it doesn't get stagnant.
An advanced option is to invest in a humidifier. These devices can keep your plants happy but are also known to improve your own health, skin and sleep quality.