If your work is sloppy then the employer may suspect that you do sloppy work and not offer you an interview. Remember, writing your resume is a continuous process that will persist for as long as you are developing professionally. It's never to early to begin. After you complete your fieldwork or practicum it is a good idea to write down your responsibilities. Collecting and organizing the information as you complete each field experience will make it easier to create a final draft of your resume later.
Resumes are extremely important.
Resumes help you to obtain an interview which gets you the job. Now that we have entered the information age it is not appropriate in the United States. Yes, if you wanted to be contacted as soon as possible. I have a home page. It depends on what is on your homepage.