The IQ level is a very relative concept, it measures, contrary to common misconceptions, not the absolute level of intelligence. It is believed that IQ tests show the level of intelligence for a particular age.
Formally, it is very easy to increase your IQ level. It is enough to train yourself to solve tests. If you need to take an IQ test at some official organization or for employment, it is better to practice in advance.
To train your brain to solve standard problems, any online test is suitable for you, in which you can see the correct answers after passing. It is believed that the more tests you pass, the better the result of each next one, because in the process you learn to properly allocate time to solve problems of each type and understand their patterns. Such training can improve the final result by 5-9%.
Problems in the test are divided into several types. Among them are text, elimination tasks, spatial and numerical sequences. For each person there are the most and least comfortable and understandable types of tasks. Take a few tests on the Internet, analyze what tasks are given to you with the greatest difficulty. Pay attention to them, when solving the test, spend more time on tasks that are difficult for you. If you have no idea how they are solved, after the end of the test, look at the correct solution and think about how it was obtained.
Try to compose these tasks yourself. Get creative. If you manage to compose complex, intricate problems, most likely you will not have problems solving such examples in the future.
One of the main factors in solving a test is time. Therefore, distribute it wisely. If some problem persists, skip it and solve the rest, in which case, if after that you have too much time, you can think about the problem longer, not to the detriment of the result. Don't be in a hurry at all. Haste makes people inattentive, and IQ tests always require attention.