Boat Ride in Bangkok and Pier locations???

Hi,

I would like to travel by boat just for the experience sake. Plus, if I want to visit Khao San Road cheaply, I can do this easily traveling by the boat.

All I know is Pratunam Pier is an interchange pier.Let's say If am I staying near Asok BTS/Sukhumvit MRT, and would like to visit Khao San Road, how can I do it?

I was reading online someone said I would have to get off at Siam interchnage and walk towards National Stadium and exit from there on my left side and I will see a Pier that will take me to Pratunam Pier? From there I can follow Golden Mount line and get off at the last pier called "Phan Fa Lilat" and a short walk from there.

I wonder if there is a nearby pier from there I can go to Pratunam pier ?

Thanks

You can see all the piers in this map of the khlong saen saep Express boat : http://khlongsaensaep.com/lines-route-map.html

From BTS Asoke or MRT Sukhumvit, walk to Klong Sanseab, then find MRT station you will see the way to Asoke pier.  Then waiting for the boat go ahead to Pratunam.  The boat will be stop there then you change the boat to PhanFha Lilas. 
From PhanFha Lilas peir you can find the way to Khaosan road.
then start to walk from Wat Ratchanadda Ram and walk along Rajchadamnern Road you will reach Khaosan Road.

Another nice trip By Chaophaya River boat :
From BTS Asoke - Saphan Taksin station, take the boat from Sathorn pier to Tha Pra-A-Thit.  Khaosan area will start from here  :)

MonJa, you are a nice addition to the forum. Very helpful information, indeed. Thanks.