Victorian English is the "typical" British accent, according to the British Library. Associated with the 19th century, and the era of Queen Victoria, Victorian English is a formalised version of the British accent. Practicing Victorian English is a wonderful way to broaden your manner of speaking. The most critical things to remember when working on the accent are speaking with proper inflections and using the proper vocabulary.
Place the accent. Push the sound and air to the roof of your mouth when speaking a sound or word. Practice this push, for example, by emphasising your "O" sounds by speaking words like "don't", "won't" or "know". The roof of your mouth should vibrate as you vocalise and hold this sound in a Victorian English accent. Bring the sound off the roof of the mouth and shoot it out through the lip. Keep the stress of the sound forced up and toward the front of your mouth -- near the lips -- as you continue speaking. Remembering accent placement readies the muscles of your mouth to function in the manner of Victorian English speakers.
Practice sounds. Begin with the sound of the letter "O," for example. Round your lips into a tight circle and force the air and sound through the opening. Practice both long and short "O" sounds until each is resonate and smooth. Purchase a professional audio training CD -- "Acting with an Accent" by David Alan Stern, for example -- to guide you with instructional recordings.
Use equivalent expressions. Reconcile terms in American English with Victorian English. Say "biscuits" when you mean "cookies," for example, or say "trousers" when referring to "pants". Knowing equivalent expressions is an essential last step to speaking Victorian English. Purchase a Victorian English dictionary to help you master your understanding of traditional terms and meanings.