A 'hump', in this context, is the same as a 'bump'. It can describe the most difficult, boring or dangerous part of a job or activity. Colloquially, Wednesday is referred to as 'hump day', because once it has passed, you are closer to the weekend. When you 'get over the hump', you surpass the most challenging part of something. This is a casual, colloquial expression.

1. The first few months of living in a new city were difficult, but once I got over the hump I settled in well.
2. I am not a morning person but I drink a lot of coffee to get me over the hump and am much more productive after 10 am.

1. We've had a lot of setbacks with this project, but we're finally over the hump now. It should be plain sailing from here.
2. I know that this is a big order to fill, but a few weeks of hard work should be enough to get us over the hump.