In the Name of Allah, most Compassionate, most Merciful

a. simply stand in your bath  and have baby bath in front of you with 4 Mudd = 1 sa ( 3L) of clean water,

b. wet your hands then wash them

c. Pour water with your right hand over your left hand and wash private area

d. rub hands with earth (or soapy water).  Most people don't have 'earth' laying around these days although feel welcome to pick up some sand from the beach next time you go to use for cleaning your hands after washing your private parts. Wash hands

e. make up a small container with soapy water

f. rinse mouth with fresh water

g. wash nose by sniffing water into it then blowing it out (not into your clean water) 

h. wash face (with soapy water)

i. wash forearms (with soapy water)

j. Now is time to soap up your hair although it is not sunnah.  

k. Pour 3 mudds (both hands cupped together filled with water) over your hair and wash down to the roots.

l. Pour 1 mudd over your body to rinse off any remaining soap/ shampoo and don't forget to save a little for your feet.

m. Step into another section of the bath and wash your feet in bath, starting with the right one.

n.  Now you can scrape any remaining water off yourself with your hand.  Some people say it is disliked to use a cloth to dry yourself as the Prophet (PBUH) refused one, but there are some weaker hadith that say the Prophet (SAW) used to wipe his face on a cloak or a small cloth as a towel.  Allah knows best.

The Prophet used to take a bath with one Sa' up to five Mudd of water and used to perform ablution with one Mudd of water.  (Bukhari)

A sa' of water is about 4 cupped adult handfuls (while a mudd used for wudu is 1 cupped handful) so don't soap up too much!  If you have accidentally put a bit too much soap on your hair then use that occasional extra '5th' mudd the Prophet (PBUH) sometimes used.   Women with long hair sometimes used up to 2 additional mudds.

When Al-Hasan complained that this wasn't enough water for him to bath with, saying to  Abu Jafars, 'I am a hairy man.' Abu Jafars replied, 'The Prophet had more hair than you'. "(Bukhari)

Abdullah ibn Mughaffal narrated that he heard the Prophet say, "There will be people from my nation who will transgress in making supplications and in purifying themselves." (Related by Ahmad)

If you use more water than is needed to wash in the order as sunnah then you are committing a sin and there is no excuses about wasting water.  Remembering though that you must get every part of your body wet.

Says al-Bukhari, "The scholars do not like one to use water beyond what the Prophet, upon whom be peace, used for ablution. (Fiqh 1.32d)