Hirers usually have very tight deadlines and cannot review all the proposals posted to them.
To stand out from the crowd, you need to ensure that you your profile page is complete and up to date with your skill sets and work experiences.
Always read and understand the job requirements before sending a proposal. If you have a question about the job, you can Ask a Question from the Hirer by posting your question at the bottom of the Job description. The Hirer will review your question and get back to you.
Please remember, if you spam the Hirer with irrelevant proposals or questions, your account could be suspended.