Item description:

Save 1
Distracting
Shoot the tannoy with your watch.
I expect you to die
Get the remaining collectables (Goldfinger)

Save 2
Boys with Toys
Buy attachments for 1 class of weapon
Spend the money quickly Mr. Bond
Continue playing. Will pop after earning some XP.

Save 3
Goldfinger
Finish the mission

Save 4
Signature
Kill a few people with the P99
People Power
Continue & collect some intel
Web of intrigue
Continue & collect some intel

Save 5
O.H.M.S.S.
Never happened to the other guy
Collect the last of the intel and finish the mission to get the above 2 trophies
Very novel Q
Continue in to the next mission and purchase the dart pen upgrades
Positively shocking
..Then take out the first 2 guys. Kill the 3rd when the 4th is walking away at a distance, then kill the 4th. Sneak to the right and shock one of the 2 people that are standing next to each other with your pen.

Save 6
You prepare for the unexpected
Collect the remaining intel (Licence to kill)

Save 7
Licence To Kill
Finish the mission

Save 8
Happy snapper
Go to the next room and take a photo of the croc below the glass floor

Save 9
Vodka martini, plenty of ice
Collect the remaining intel (Die another day)

Save 10
With or Without Q
Drive along the right wall and steer sharply towards the plane in the last few seconds
Standards of physical perfection
Purchase all the training modules

Save 11
Die Another Day
Finish the mission

Save 12
Scream if you want to go faster
There is a guy in a gyroscope behind a window on the left. Hack the WIFI panel that is behind him.
Making it personal
Around the world one more time
Clandestine
The above 3 kept popping before I could make individual saves. Keep playing the level getting the remaining intel. I think there are 2 remaining before you go inside the office, inside the unvisited 'section 2'. You will go there when you are looking for the switch to unlock the office door.

Save 13
One small step for man
Continue. Cannot be missed.

Save 14
Moonraker
Finish the mission
Secret Agent
Finish the mission

Step 2:
Now you have completed the campaign, back out to the main menu and do the first challenge mission. use default settings and just run as fast as you can. You are aiming to get 3 stars.

Save 15
Shooting star
Get 1 more star

Save 16
Star struck
Get 1 more star

Save 17
Challenger
Get 1 more star
Fascination with all things gold
Get 5 stars in the last challenge

Step 2 Alternative:
I have included a save for all challenges complete. This might pop all of the star trophies when replaying a challenge.

Step 4:

Save 19
Above and Beyond a 00
Go to mission select and do 1 more trial 007 trial
Everything or nothing
Go to mission select and do a trial on a mission that only has 1 trial missing

Save 20
More than an agent
Continue the campaign. When you begin your escape, shoot the target in the 2nd doorway on the right