..... Well she can't help it, she just has a knack, maybe because she has so many (I'm sitting here turning green with jealousy as I write), (Mwah!!!).
Where are you anyways Eve? You agree, right? 
The coloration (males are brighter) and a wider base to the tail are a give-away. Females have kind of round tails all the way to their hips, the males have a bulge at the base of the tail, I never read it before but personally I think the base of the tails on the boys is almost more of a "Square" shape, in the Easterns at least.
All of my collareds try to jump up at the UV light, I have to use a tube inside the tank instead of a round bulb above the cage. I find that if the UV light goes off before the basking light, they jump up and smack their heads off the basking light instead which is suspended from the ceiling, dangerous if it's hot !!
Therefore I time the lights to go off together. They still climb for the UV light but it isnt warm enough to burn them, so I provide a shelf that is a few inches below the UV light. They tend to sit on the shelf and tilt their head against the bulb, I never understood why they do that but at least they don't bump their little heads on the ceiling anymore, lol
Also, when I got my first pair they were both males, I noticed that if they got too close to one another they would both head bob at each other, lick and part company. Unfortunately I had to take one back, and ended up with a gravid female instead. Anyway, I'm sure you'll be fine, you're in the right place if you have questions, thats for sure 

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Kel
www.collaredlizards.co.uk
0:0:1 Timor Monitor
2:2 Collared Lizards
1:6 Green Anoles
1:0 Dune Scorpion
3:0 Imperial Scorpions
2:0 Desert Hairy Scorpions
0:1 Mexican Red Knee Tarantula