Perhaps you've just graduated from college, started your first job, rented your first apartment or purchased your first home. It's an exciting rite of passage. Part of the excitement relates to the opportunity to make a space your own, infusing your taste and design sensibility. Thankfully, good design doesn't have to be expensive, and there are a number of easy and affordable ways to make your pad feel fun yet sophisticated.

High contrast: Sometimes a single-color palette can come across as unsophisticated. Try using high-contrast combinations, such as black and white, light and dark, which can seem more luxurious.

Pastel colors: Pastel hues, both youthful and sophisticated, are back. Don't be afraid to use soft blue, pastel pink or mint green.

High vs. low: Designers do it on the runway, so why not do it in your home? Mixing more expensive pieces with flea-market or thrift-store finds can be a fabulous way to create an overall sophisticated look.

Decorate with books: Decorating with books is one of the most affordable ways to design, and a go-to designer trick. One way to display books is to turn them spine-in to create a consistent look.

No stuffed animals: Stuffed animals are a no-no if you want your space to feel grown-up and sophisticated. If you can't bear to part with them, consider placing them in a decorative bin.

Add greenery: Plants, succulents, florals and trees are good for your environment and a great way to infuse color and sophistication into your space at an affordable price.

Go for glass: Glass pieces of furniture are often a fraction of the cost of wood pieces. Glass coffee or dining tables can help create an open, airy feel at an approachable price.

Purchase quality large pieces: If you can afford it, try to buy one or two high-quality pieces you intend to own for years, if not decades to come. Some ideas of where to start include case goods such as armoires or dressers, beds and sofas.

Consider leather: If properly maintained, leather can be both long-lasting and add an element of maturity.

Inexpensive artwork: Artwork is like the icing on a cake and can help a space feel complete. Framed art tends to look more expensive than pieces that are not. Some ideas for inexpensive art include framing pieces of fabric, posters, calendars, wrapping paper and even postcards.

Framed photos: Whether they are from a vacation or your own collection, framed black-and-white photographs can be both interesting and mature.

Add mirrors: Especially in smaller spaces, mirrors help to open a space and add reflective light, almost like windows.

Cathy Hobbs, based in New York City, is a TV host and interior design and home-staging expert.