I started modelling my alien character about a week ago and I have now gotten to the stage where I am just adjusting the topology to ensure the lines flow correctly, this not only produces a cleaner model but it will also help the rigging, weight painting and animation stage. Modelling a quadruped was something new to me so I made sure I looked at reference a lot of the time to get a better understanding of the shape and build of an animal. I really benefited with the advice I got from my friend Jacob as I would send him images of my model and he would give me feedback of what I could improve. I also learnt a lot of new tools and techniques with the modelling workflow e.g. duplicating half of the model as an instance, this allows you to adjust one side of the model and it will do the same on the duplicated half. This is a good way to work as you can constantly see the transitions you make and don't need to keep mirroring and deleting faces. The sculpt tool in Maya is a really quick and useful tool which helps you even out the edges of your model, it makes it a lot cleaner, before I did this the mesh was quite messy and I would not have been able to take it much further without cleaning it up first.
You can see the stages of development from the pictures below and I'm quite happy with how it's turned out, it still needs tweaking here and there before I am able to move onto rigging. As you can see the tail was originally down but I was advised that for rigging purposes it would be easier if it was modelled straight. The one thing I could have done different is the way I attached the legs, ideally they would have been attached to the side of the body and the edge loops would have flown a lot better; but instead I connected them to the bottom of the body like I would with a biped character. Hopefully this shouldn't impact on it too much but I shall have to bare this in mind for next time.