You will be sent an email when the gedcom has been processed. You then need to go through the list and mark EVERY suggestion as a match or reject. if you match a suggestion you can edit the match and merge your data with that profile.
When that is finished the ADD button will appear beside all the remaining persons. You then start adding each person. The biggest job in this phase is formatting the profile.
One last think, after all of the above you need to go through the list one more time to ensure all the relations are in place because the process does not make some like connections to the matched profiles and multiple marriages.
Good luck, entering a 1000 persons is a lot of work. Caution, you need to keep working on the file. If the file is not touched in 90 days, it gets deleted.