I am no expert in designing but, starting as a designer can make you anxious and you may feel how to enter this field of design because I went through the same mindset. I think that design can be best learned from working on projects and you should be involved fully in those projects. If you are doing your own project for portfolio then you should first learn the process of the design and it may take time at first but as you move through the project you will get to used to it. Keep some time for understanding and analysing the projects of others then, try implementing the same process. But, don't just copy the steps think what is the purpose of those steps for e.g. what is the use of usability testing, how will it have an impact. If you just copy the steps without understanding it deeply then, you will be using it but that will not improve you as a designer. You can copy the designs at first from behance, dribbble. Later on once you are familiar with layouts, grids then you can move towards achieving something different in UI. There are a lot restrictions while designing a UI so, its better to learn about it which will help you in understanding about layouts in general and the guidelines that the designer needs to follow while designing UI.

 

Keep in mind that  designing a great product takes time. A designer should keep on learning on daily basis try reading books on the designing field you want to pursue or you can also read books on strategic design and UX design which also helps the designer to think about the business. Understanding the business is important for a designer. Don't think that you will need to learn all the software in the industry to make you a better designer. You just need to choose the tools that you can use on all the platforms and that you are comfortable with. Learn the basics of one or two software and then hone your skills by practicing the software and learning the shortcuts( they save a lot of time!). So, keep on practicing and learning.