I've always prefered lsd first. I'd wait a little later in the day to take it though, as sunshine can wash out some of the more aesthetic qualities, and I like to experience both sunlight and darkness while tripping. Another reason to wait a little later to take it would be to avoid the drained post-trip feeling before going out. If you take the L between 1 and 3, and the MDMA between 10 and 12, you'll probably avoid, or rather delay until the end of the MDMA experience, the brain mush feeling you can get at the end of a trip. But thats just a guess, these types of substances treat everyone differently.
My personal favorite way to take these two chemicals is L first, then 3ish hours later the MDMA, this seems to extend and amplify the LSD peak then morph into an experience entirely different than either chemical alone. Have fun and be safe!