After getting the decoder kit from Director D, go talk to the spy on top of the HQ building. In code, he'll tell you that when you ask Dr. Spyglass for an eye exam, you should pick the letters that face in the opposite direction.
Go to Spyglass Eyewear (it has a huge Groucho Marx disguise on the front). All the way to the left, Spyglass is waiting. He will give you an eye exam and for each symbol he points to, you should choose the one that faces the opposite direction (M instead of W, 3 instead of E, etc.).
Then he'll leave and you can exit the store and enter through the door on the second floor outside. Spyglass will give you a camouflage (chameleon) suit that turns you invisible whenever you stand still. You can use this to get past the guards and dogs at the Docks.
get the invisible suit on and go past them
be invisible.
When you are wearing the Chameleon Suit, you are invisible when you stop moving. You can slip past the guards and dogs using it. (see related question) In the Bistro, you need a chef hat to get the wine glass. When you get it, slip past the guards by going through the kitchen vent and across the light fixtures.
You can slip past the guards to get to the roof, and past the guard dogs inside, if you have the "Chameleon Suit" that makes you invisible. You get it from the doctor at Spyglass Eyewear. (see the related question)
When you are wearing the Chameleon Suit, you are invisible when you stop moving. You can slip past the guards and dogs using it. (see related question) In the Bistro, you need a chef hat to get the wine glass. When you get it, slip past the guards by going through the kitchen vent and across the light fixtures.
At the docks, you will need to be invisible to slip past the guards. Get the Chameleon Suit, then move slowly and carefully past the guards and dogs (you are only invisible when standing still). At the Rooftops, you get to the tallest building by going farther left to the red building, climbing up, then grappling back to the right. (see related questions)
Use it to rescue the first kidnapped spy, who is being held at the docks to the left of Main Street. You can use the suit to slip past the guards, and past the dogs inside the warehouse.
You have to get a balloon.
with the camo suit
4
There are no guards at all on Lunar Colony. PASE doesn't have any money in the budget.
Just as you slip past the guards outside : by moving when they are not looking. Let the dog walk away, then wait and move toward him, leaving enough time to come to a complete stop (to stay invisible). (see related question)