I don't know how old you are, but I'm in my 20's and I'm not worried about it. Most of the following is highly speculative, but predicting the future always is. Let's look at ways of extending life that we're already working on:

1) Growing artificial organs from our own cells so we can replace your heart as easily as your car's brake pads.

This guards you against trauma, cancer if you catch it early, heart disease, etc. It even guards against old age itself to some extent, although you'd still have Alzheimer's and Parkinson's and the like to worry about. This is maybe 20 years away from being widespread, at least for major organ transplants.

2) Stem cell research

This promises to deal with most of the remaining "old people" issues such as Alzheimer's and Parkinson's. It's especially important because living a long time wouldn't be worth it if you can't remember breakfast.

3) Freeze yourself like Walt Disney until we develop effective immortality.. You need money, but it can be done.

4) Go live on Newt Gingrich's moon base when you get old. The lower gravity will allow you to live perhaps decades longer than you otherwise would have, and more comfortably as well.

5) Brain transplant

If we can accomplish a brain transplant, you become basically immortal, although stem cells might be needed to keep the brain healthy. We could hook your brain up to a clone of your body, and you could live another biological life, complete with the memories of your last one. Or, we could give you an android body like Data from Star Trek, and your consciousness could exist forever without needing to poop.

So, all of these technologies and advancements extend human life, and possibly significantly so. Cloning our own organs will be particularly useful, as it fights old age itself, but it doesn't get us all the way

Now, let's the tech (still in its infancy)that could ACTUALLY make you effectively immortal: telomere research.

Basically, if we can figure out how to manipulate telomeres, we can just tell our cells not to grow old and die, and they will comply. This would be the fountain of youth, so to speak.

Edit: Because incomplete