The old and new sit side-by-side. On the right is the new PC. On the left is the old one.

And sitting in front of them -- typing away at this moment -- is an idiot.

You'd think, after all these years and all those computers, that changing from one computer to another would be a seamless process for me.  But I'm two days into the process and I'm still  hopping from one computer to the other, just to get my work done.

Today  I can help you avoid some of the pitfalls you face when you replace an old computer and move your data and programs to a new one. It's OK if you stop and snicker at me along the way. I've made a mess of things. But that's why I'm writing about all this now, while it's still fresh in my mind. There's no teacher as effective -- and cruel -- as personal experience.

Let's take things in order here, because your work toward the move from the old to the new should start before the new computer is even purchased.

Get your house in order

Since the arrival of a new computer is distracting -- after all, you want to plug that sucker in and see how it performs -- the best time for your preparation is before it arrives on the scene.

Even though you've been doing regular back-ups of your data, now is the time to make sure your backup contains all the data you want to transfer. So check the settings on your back-up to make sure  all the folders of data you need are included.

I  wish I had done that. After moving my backed-up data to the new computer, I was forced to go back to the old one three times to gather data I'd missed. The list of things I forgot is too long to rehash, but it included the bookmarks for my browser, family photographs, information I need to log on to  systems used to deliver my columns and spreadsheets of finance information I had (on purpose) hidden away deep inside some folders.

You'll also want to assemble all the installation discs for the programs you'll use on the new computer. Conventional back-ups only contain data, not the programs you use. Also make sure you still have any activation codes needed to install those programs. I thought I had done all that. But when I started working on the new computer, I found that several programs I needed were missing. That involved searching through closets, bookcases and two plastic bins full of DVDs and CDs.

Do a little housekeeping during the time before the new computer arrives. You'll need extra space, since both machines must be up and running when you transfer data. Me? I  counted on dumb luck and figured I could find the desktop space on a desk in my grown stepdaughter's old bedroom. I plopped one of the computers down on that desk and knocked off a small wooden chest that contained seashells she had gathered as a child. That instantly transformed them into fragments of seashells.

Follow a few simple steps

Take advantage of the tools Windows includes that automatically transfer  information directly from one computer to another. With Windows 7 (the program that will be installed on your new computer) you get that option when you first turn on the new computer. Or you can go back to it by pressing the Start button, then selecting the menu item labeled "Getting Started."

I was way too smart to need that, and that was dumb. If I had taken advantage of that first step, I wouldn't have spent time switching back and forth to find my photos, bookmarks and the like. Don't follow in my shaky footsteps: Use the transfer process. It will let you perform the transfer using your home network, or discs, or by connecting the two machines directly using a cable.

Plan on keeping the two machines connected to the network and capable of running for several weeks. While you can do a better job than I did of assembling the data for the new machine, inevitably there will be files on the old machine that didn't make the move. You won't notice that until you need one of them.

Do this right away

Get an anti-virus program, along with a program to search out adware and spyware, installed on the new machine immediately. My clear favorite for that is Superantispyware (www.superantispyware). I use the for-pay version myself but the free version works great too.

Things not to rush

In my case, I plan to eventually install a different video card in the new machine. I found a bargain of a computer but, to get that price, I had to take the PC  in the configuration that was offered. And that included onboard graphics instead of a separate graphics card. I enjoy a few computer games and a separate graphics card does a better job with games.

But -- and this is one thing I did right -- I am using the computer without that card right now. There's enough confusion between setting up the new computer and getting some work done without complicating the task by opening up the new machine. And even something as simple as installing a video card can go wrong. So I'll leave that for later.

(By the way, I'm impressed with how good onboard graphics is these days. While I've always told readers to buy a machine with a separate video card, I think many of you, especially if you don't play many computer games, can do just fine with modern onboard graphics.)

OK. I'll stop now. After all, there are still things to do here at Technology Ranch. For instance, I've just discovered that all the information I need to send in  this column can only be found on the old computer.

I often end a column by suggesting that you save it for a day when that information may come in handy. Today, considering the miserable job I did in making the transition, I'm going to save this one myself in the hope I'll do better next time.