(Permission obtained from Obsidianpony.)

Coming up with a custom species is easily a major challenge. Inspiration is hard to come by. The idea might soon seem stupid. But once you have your idea, stick to it.

Inspiration is the key to creating a custom race, and in terms of where to look, nature is our best friend.

Look at all the animals on Earth. Any of them can provide a basis for your Original Species. For example, you may want to create a large reptile race that in spite of its strength is a bit clumsy. Alligators easily provide the strength portion. In terms of clumsiness, the best I can think of is a type of constrictor snake. In spite of their strength, constrictors are very heavy animals, and therefore can be very clumsy if they miss their prey entirely.

If you want speed, there are many animals to choose from. If you are again looking at reptiles for two species to combine for your species, the Spiny Tailed Iguana is the fastest. However, if you want this species to also be venomous, the Gila Monster is your best bet if you're keeping yourself restrained to lizards for inspiration.

In terms of taking inspiration from other animals, it's endless. You might want to combine the size of a Blue Whale with the intelligence of a Chimpanzee, and have the end result look like a gorilla.

If you want to find machines for your species, what better place to look than science fiction? For me, science fiction has been a master inspiration source, and to me, it is the best out there. You can also find species inspiration, too. What about a fat slug like animal that has a sharp tail and an inner jaw? The Hutts of Star Wars and the Xenomorphs from the Alien franchise each fit the bill, with the Hutts being slug like and the Xenos having sharp tails and an inner jaw.

Most importantly, though, make sure the inspiration won't leave your mind, and when you've already got one species down, try and detail it's features on paper and such.

That's all for now!

This could also be a good source of inspiration http://www.fimfiction.net/group/197119/worldbuilding-alliance/thread/65509/world-building-halfbreed-races

2325137
Agreed.

2324895 Baticorn.

2326695

Bats, horses, and possibly Rhinoceroses if you want the hon to be big. If not, you can easily draw from the Lunar Guard.