Training Construction (Level 1-30)

Get started:

Go to the Estate Agent and buy an house.

Getting Supply:

All the supply you need can be bought from the Sawmill Operator who is found near the Lumber yard, northeast of Varrock. To make planks you will need to bring him the logs and money.
Go to Varrock west bank, wield an axe and grab 2.8k* cash in your inventory (rest of inventory is empty). In the way to the sawmill operator there are a lot of normal trees and oak trees so cut them and fill your inventory with logs. When you close to the sawmill operator drop one log and woodcut another one. Buy-Planks from Sawmill Operator. Drop 1 plank, pick the log you dropped before. Trade it for plank as well and pick the plank u dropped. Now walk back to Varrock west bank.
Do few trips until you got at least 89 planks (to get you up to lvl 15 and build Wooden workbench).
After you got enough normal planks do one more trip to with some cash to buy nails and 1 saw so you can build furniture.

There is also a way to get normal planks for free. You can collect them in 2 places I know about:
1. Entrana, next to the law alter (west from it) there are 2 normal planks you can pick. So if you making laws or run laws after every trip you can pick 2 or more.
2. The other place is more risky but faster – Graveyard of shadows at wilderness lvl 20. There are 4 normal planks around there (if I am not mistaking).
Nails can be made by smithing.

* If you making oak planks take 7k gp instead of 2.8k gp.

Levels 1-14:

Supply needed:
84 Planks & Nails. (5k gp optinal to move your house to Taverley).
(get more nails because u can lose some. The better the nails are you lose less nails – I never lost nails when I used mith nails.)

What to do:
Your house should be at Rimmington. Go Falador (west or east) bank. Remove everything you wear, Put boots of lightness if you got. In your inventory put hammer, saw, nails and normal planks and run/walk to your house at Rimmington. When you enter your house you will have only 2 rooms, Garden with exit portal and Parlour. Change to building mode (or enter with building mode). Go to the Parlour and start build and remove the best chair you can build. Do it over and over again.
When you out of planks go back to Falador bank to get more supply.
When you got construction level 10 you can move your house to Taverley and use Rogues' Den bank.
You can avoid running to bank and bank if you bring all your planks noted and sell the planks to Rimmington general store and buy back.

Levels 15-30:

Supply needed:
5 normal planks & nails, 183 Oak planks and 10k gp.

What to do:
When you get construction level 15 it is time to make your house a little bigger. This bank trip bring hammer, saw, 10k gp, 5 normal planks & nails and rest inventory oak planks.
Enter the house in building mode and add a workshop to your house (recommended to add in one of the 3 doors of the garden).
After adding the workshop to your house go to it and build and remove 'Tool store 1' until u reach level 16.
When you reach level 16 build and remove 'Crafting table 1' until you get to level 17.
When you reach level 17 build 'Wooden workbench'.
Now keep build and remove 'Crafting table 1'. Keep doing so until you reach level 19.
When you reach level 19 you have the ability to bring and use 28 oak planks a trip. How? Now you have workshop with 'Tool store 1' and wooden 'workbench'. 'Tool store 1' will supply you unlimited number of saw and hammers. So here what you do: you enter the house with 28 oak planks (normal entering not building mode). You go to the workshop drop 2 oak planks and take 1 saw 1 hammer from 'Tool store 1'. Now you using the 'wooden workbench' to make 'oak chairs'. You make oak chain, drop the flatpack oak chair and pick the 2 oak planks you dropped before.
Keep making oak chairs/Oak table until you get to level 30.

Level 30+:

Congratulation you reach level 30, you in high score !!!
It is time to start plan your house and work on it.
Before start to plan your house you should read Home Design Tips.
You can use RS Home Designer to design your future house.