weird lumps that look a little like grey-ish peas. The longer the tick is clamped onto the dog, the fatter is gets (swollen with blood) so easier to spot.
I try to check mine carefully but last night i was giving sally and cuddle when i felt one through her fur. so they can sneak up on you! don't beat yourself up, I have removed three this week! (and have left a panicked message in springer health

)
The male is sometimes arounds where the large female is, so have a look through the fur and try and get rid of that too.
I find the most common places seem to be on the head, ears and once between the toes!