1) Persistent contrailing altitude (no NOT chemtrails)
2) That was done by an excellent stick and rudder pilot.
I don't care how good of a pilot you are, there are never atmospheric conditions that create such a sharp and dense contrail, but totally disappears with just a few feet of altitude change. And those would be the conditions necessary to instantly start and stop a contrail that precisely.
In order to make that figure in the air, a smoke generation system would have to have been used. Injecting diesel into the exhaust manifold is how skywriters do it.
The Blue Angels (and Thunderbirds, etc.,) do have special smoke generators on their demonstration aircraft, but unless they were visiting NAS Whidbey Island that day, no Navy aircraft made that aerial figure.
Fairly easily actually. If it was an F/A-18G such as what VAQ-133 fly out of Whidbey island all it would take is to enter four or five waypoints for pinpoint navigation and fly the pattern on the HSI to each point clocking the turns.. It was basically a figure eight with an attached parallel course and 180 turn. Similar to a Marshall holding pattern. Probably named the waypoints Trojan, and big Jim and the twins.