I’ve freelanced a bit on Upwork strictly for data scraping and data science. And I’ve hired freelancers with the site too. I answered this question on Quora and wanted to share it here for everyone too.

You may be overwhelmed by your competition and lose faith but I hope I can offer some encouraging insight. The hardest project to get is the first one

1. Tailor your proposals. For most applications there is a flood of applicants spamming a generic cover letter — I’m so and so and I did this etc… Some employers combat this by adding line in their description saying to mention it so they know you aren’t spamming. Already you can stand out by doing solid research on the applicants description and tailoring your cover letter. Use their name if you can find it (you can find this on past reviews from freelancer). Mention specifics about the project
2. Select projects within your credibility. Unless you have a great consulting website with past testimonials you should start with small contracts that require little oversight. The problem is clearly defined and if you can convince the client that you can solve it you got the gig. Once you have a solid track record you can get larger projects. I’ve found it helpful to work on small projects before getting the gig to build my portfolio and skillset even if I don’t get it
3. Don’t under or overbid. From the client’s side he/she will see many proposals and you don’t want to look “cheap”. Say the web scraping you need to do typical goes for $30/hr. If you bid for $10/hr you might think that’s a positive think but in reality you will look cheap and tarnish your value. (Read Thinking, Fast and Slow: Daniel Kahneman for more info on this phenomena as well as other cognitive psych.)
4. Research your clients. Don’t apply for a fixed bid project for a client who has had issues paying or has never paid before. Turn it into a milestone project. Good clients will appreciate your input. Work for people that value you and what you’re worth

Also a few other notes for Upwork. If you speak the language of the host fluently that can do wonders. Constantly look at other freelancers hired by prospective clients in the past. You’ll be able to see if it’s worth bidding on and assess your skills relative to the market. Sometimes this is an ego-boost and sometimes you can be really impressed by the competition. Best of luck!