Every human being has some skill sets from by birth and some by practice or education. Similarly software testers should have important skill sets and we will explain the skill sets only in this article.
Knowledge level
A tester should have an extreme knowledge level where he excels in thinking, communication, latest techniques in testing, learn latest tools in his fields. He/she must compete to learn along with developers the new technologies under which development is being developed. He must have the ability to analyze and communicate what he has analyzed. The skill set learned or improved upon every day will make a tester also earn very well.
Understanding Requirements
A tester's first and foremost duty is to understand the requirements. For this a tester must be in the mentality of the business people, should understand the business terms and functionality and only then can he test the application or whatever has been developed. A developer will develop whatever is requested by the Bas, whereas as a tester we can't be dependent upon the Bas. If dependent then the application condition will be independent. There must always be a clean and clear vision of the requirements. Similarly there must be a situation where testers should adapt for the changes in requirements. There will be many changes and challenges where testers should be ready to experience them all.
Planning
An idea/activity that is unplanned will always will be in trouble without any solutions. Here as a tester we need to plan well and execute them very well. Here we are responsible for estimation, writing test plans, testing methods and so on.
Test Design
This is a case where the main work of a tester starts and his skills will be fully used. A tester must design as many test cases as possible. He/she must not only design two or more test cases, they must dig a well until they see a rock below. That is all the possibilities should be finished off during the design.
Test Automation
There is a new type of testing called automation testing where testers write a separate script to test the application where it will operate automatically as per the code created. This mainly reduces the time, cost and human errors during testing. But this cannot be an ultimate solution when humans are involved. Anyhow, this will be very useful during regression testing, testing multiple orders, data driven testing and so on.
Test Execution
This is the skill set in which a tester should be very calm during execution and relax run all the test cases but deliberately. There must be a purpose during execution where finding various numbers of bugs must be the ultimate target. Execution is the place where a tester can learn a maximum number of functionalities, testing designs, techniques, ideas and business knowledge.
Reporting
A skill set that many testers have less of is reporting. Here only decides whether a person is a good tester or not. Reporting is a way to express the status in which a tester submits his work and shares his ideas. He needs to report to the BA, client, developers and even the CEO. So the reporting here must be concise, accurate and also precise in size. That should be a formal one and good to read. Whoever views them must understand. A reporting will be a mirror face value of a tester. The person who is been reported must be able to gain knowledge on what you are trying to say/report.
Team playing
People think that this doesn't deal with the testing profession, but this one tops on the table, where a tester must maintain a good rapport with developers, BA and also to the client if applicable. They should learn from their teammates and share what's the update respectively. It's not the place to fight or war is happening, all are working under specific motos and we are on the quality track so we must deal them properly without quarrelling with anyone.
Process improvement
There must be improvement every day with all the tasks, attitudes, approach, skill sets and so on. If there is anything newly implemented just grasp some knowledge on them and share it with others. There are many mistakes to be done, don't skip on the same mistake or do them multile times. Learn even from mistakes.
Time management
A very good skill that matches all the professions. We developers or testers work the same on agile methodology at the present where we get very minimum of time for developing to production. Meanwhile as a tester we must plan, organize and prioritize then execute well. Not every player who has run a 100 meter race is not awarded with world record, person who completes within the record time is been awarded. Similarly life is a race, we all must run and here the time plays a major role. This time can bring a tester a good time or else bad time also. So he must plan and execute well with the given time.
Thus some of the skill sets I have specified along with the definition for them that all the testers must need and follow in their profession.