When planning your trip to London, allow for a minimum of 6 to 8 days. 10 days is ideal.
Bring your most comfortable shoes, and shoes that provide cushioning. You’re going to be doing a lot of walking and standing on hard floors.
Use the audio tour devices at tourist attractions that offer them. You’ll gain a wealth of knowledge about the tourist attraction you’re seeing.
Always take a backpack with you, and be sure to have in it the following items: an umbrella, an extra layer for your upper body, a jacket, a portable power pack for your phone, a bottle of water, energy bars, and a packet of pain reliever like Advil or Tylenol.
Probably most importantly, allow enough time to see the sites you’re visiting and plan accordingly. Some of the sites take much longer to see than others. This is where I can be a tremendous help to you!