UPDATE: Due to the recent patch, some of these building tips no longer work correctly.
This video features a collection of 50 tips for building settlements in fallout 4. You can easily skip straight to what you're looking for by selecting the links below.
00:55 - 01.) Local Leader Perk
01:09 - 02.) Force Foundations Through Ground
01:19 - 03.) Water Purifiers on Land
01:37 - 04.) Stacking Foundations Vertically
01:48 - 05.) Snapping Difficult Objects
02:02 - 06.) Placing Decor
02:16 - 07.) Performance Issues
02:36 - 08.) Problems when placing Doors
02:48 - 09.) Stacking Floors Vertically
03:16 - 10.) Building Steps
04:03 - 11.) Forcing Foundations through Others
04:15 - 12.) Floating Floors Drop Straight Down
04:47 - 13.) Precise Rotation
05:00 - 14.) Snapping Prefabs
05:14 - 15.) Stacking Objects inside One Another
05:26 - 16.) Generator Comparison
05:48 - 17.) Lights on Objects
06:12 - 18.) Fixing Lights
06:32 - 19.) Largest Settlements
06:57 - 20.) Settlement Starting Sizes
07:17 - 21.) Keep Terminals Separated
07:41 - 22.) Stacking Delay Switches
08:09 - 23.) Power Counters
08:26 - 24.) Fast Travel Welcome Mats
08:39 - 25.) Rocket Turrets are Dangerous
08:50 - 26.) Moving Objects without Moving
09:03 - 27.) Moving Groups of Objects
09:22 - 28.) Making False Floors
10:27 - 29.) Indenting Walls
11:12 - 30.) Rotating on different Axis
11:25 - 31.) Moving over over a 1/2 step
11:49 - 32.) Rug & Mats Trick
12:11 - 33.) TV's in Walls
12:37 - 34.) Windows
12:59 - 35.) Ambient Lights for Windows
12:25 - 36.) Clearing out Crops
13:46 - 37.) Legendary Freefall Armor
14:27 - 38.) Making Caps $$$
15:11 - 39.) Materials (Wood, Concrete, Steel)
16:03 - 40.) Replenish Vendor Stock
16:44 - 41.) Size Limit Glitch
17:29 - 42.) Objects vs. Size Limits
17:52 - 43.) Unlimited Light Power
18:11 - 44.) Connectors on Mats
18:42 - 45.) Building Curves
20:09 - 46.) Hiding Power
20:22 - 47.) Lights in Walls
20:40 - 48.) Using Wires as Aesthetics
20:58 - 49.) Wires no longer require Copper
21:14 - 50.) Magazines to unlock More Settlement Options