If you are doing any sort of affiliate marketing then it is very important to go to the effort to clean up and shorten affiliate links.
It is a common mistake amongst beginners to use long meaningless URL's in blog posts and emails, but unfortunately this is not very professional and tends to weaken your conversion rates. There are three reasons for this which are as follows:
They actually look like obvious affiliate links (some people will not buy if they know someone else is getting a commission)
2. They look long and ugly, difficult to verbally describe, and they also don't actually mean anything
3. In a lot of cases you are unable to track the results of the link (but in some cases you can)
As an example an ugly affilate link would be something like this: http://www.TrafficGeyser.com/cmd.php?af=51444
It is fairly clear to anybody that this is an affiliate link, but we can clean it up to look like this:
This looks much more professional and it is not as obvious that it is an affiliate link.
Some people will suggest that the methods below are sneaky and trick people, but if you only promote products that you truly believe in (and know they are great value), then I don't see any problem with it.
From my experience there are three different ways to shorten affiliate links and make them look nice, without upsetting Google in the process
1. Use a free shortening service such as bit.ly
With these services it is simply a matter of copying your original URL and pasting it in, and then getting a shortened link given to you straight away.
Most of these services will allow you to customise the link as well, so instead of using http://bit.ly/ighwuh, you could change it to read http://bit.ly/TrafficGeyser (providing that extension is not already used by someone else).
The great thing about using services like bit.ly is that they allow you to track your links to see how many people are clicking on them, and where these people are from.
2. Forward a domain to your URL
This is a much cleaner way to shorten affiliate links than using a shortener service, but on the down side you have to pay for a domain.
To do this simply go to the Domain manager of your domain provider and select the relevant domain. From here there should be a "Forwarding" option somewhere, and once you get there, you simply paste in the URL that you want to forward the domain to.
So instead of using http://www.TrafficGeyser.com/cmd.php?af=51444, you could buy a domain such as http://GetTrafficGeyser.com (just an example).
The idea here is that people click on your http://GetTrafficGeyser.com link and then get forwarded to the real URL (http://www.TrafficGeyser.com/cmd.php?af=51444)
The only problem with this method is that sometimes the real URL (your actual affiliate link) will display in the browser address bar anyway, and it sort of defeats of the purpose.
3. Use a free plugin called Pretty Link Lite
In my opinion this is by far the best option, because you get to use your own domain and can add anything you like as an extension.
The plugin is called Pretty Link Lite and is free. There is also a premium version with extra features which you have to pay for, but in my opinion the free version is more than suitable (and is what I personally use).
The plugin is dead simple to use, you simply paste (or type in) your original affilate URL, and then choose what extension you want to use.
So for our example I have created http://lowcostmarketingstrategies.com/TrafficGeyser as my affiliate link for Traffic Geyser.
This method also makes it really easy to verbally tell someone where to go on a phone call or an audio recording, compared to the original link, http://www.TrafficGeyser.com/cmd.php?af=51444.
There is certainly no rule that says you must shorten affiliate links, and it is fine to choose not to bother. Many people don't bother with it, and still get great results.
But, in my opinion it is worth doing as it looks far more professional and cleaner.