You do not need an Alpha/Beta software product to do usability testing. In fact, if you wait until then to do usability testing, you have waited too long. This late, making changes based on usability feedback will be costly and time consuming and apt to break something else.
The resistance offered by a software developer to change is directly proportional to the number of lines of code he has written. So the best time to do usability testing is before anyone starts coding anything. Make a bunch of images that show the proposed UI and create a click thru either using html pages (drop me a comment if you want to know how) or using powerpoint.
Then test with a bunch of your prospects/customers. Your customers/prospects should jump at a chance to see a preview of what you may be coming out with. Two things will come out of this testing:
1) You have nailed the usability (great position to be in, but very rare)
2) You will uncover some small or large usability issues.
Great! to make these changes is inexpensive, it will involve only your time, not that of your team. I don’t mean you are cheap, but in relative terms it is just your time.
Here are some guidelines to do usability testing with early mockups
1) Think about the main personas and their main use cases
2) Create mockups for these use cases
3) Never lead your audience – ask your testers to tell you how they would do the task given the mockup – if there is a large deviation between how they think they will do the task and how you will let them do the task – you have a serious usability issue.
4) If they tell you that they like something or don’t like something, ask them why – in either case, you need to know why – this is a wealth of information that will help you later when the product is built. You may even uncover some unique use cases by probing your testers here. You may hear things like – “Interesting, wonder if we could use this product to do X, Y and Z” or ” Hmmm, not sure if we would want to do this because later on we may run into problems A, B and C”. – again, great insights to get early on.
As you are doing this, ask them for their value proposition for what they are testing. Do they see value in it, if yes, what and why? If not, why not?
It usually takes only about 5-8 testers for you to see usage patterns and convergence of issues. If you see issues very early, quickly fix them before you continue to test with the remaining testers.
This is something I have successfully done for a long time with great success. Not doing usability testing very early on, is leaving things for chance. All you really need is some jpegs, a web conference tool like webex and 5-10 testers for you to work a lot of kinks out of your product early on.
BTW, invite your developers and QA testers also to these usability tests so that they are participants. This way you will get less resistance later because they will better understand the insights behind the UI that you will be asking them to code/test soon.