Getting First order looks like a very difficult task but actually it is not. now i am going to tell which things you should do to get first order
All the buyers not post buyer requests they just search for service and click to gig. The most important factor to get a click you need a very image. You have to think that you need a video or not. Adding video just because there is an option is not worth. Think if you are providing SEO service then you should not upload a video because it is not suitable but if you are providing a logo design service then you should upload.
After you get a click to get the order the customer will first read the description so always mention all sub tasks which you are able to do so in case customer ask for custom quote he will know that you can do this.
while you are new try to provide the task as soon as possible. Make it cheap as possible and increase the quality.
You can give free support for some time to the customers. if you will do so that customer have a new task he will consult with you first and you will have a chance to get a task again.
Use buyers request wisely. Read them completely while writing the offer always mention the tasks which were present in the request. Dont just copy paste.
if you have any question please ask me