Dear Cindy,
Although I have not done any ocean freight (my experience lies in commercial air freight) or relocations, I can help you with a bit of information
1. sort your items (classify)
2. make a packing list of the items (classify the articles so that you do not have to keep searching for items on the list)
3. get hold of cartons, that are sturdy
4. it is a good idea to waterproof them on the inside (I am not a fan of plastic, but your goods are valuable to you)
5. Number the cartons (either use a pen with water resistant ink or paste the numbers (BIG FIGURES) on cartons
6. Keep a separate list of the cartons. This list will carry only the classification (header) and the dimensions
7. Keep the dimensions in the sequence : Length x Width x Height and weight (use a spreadsheet on your computer)
  (item number | Carton number| Category | number of cartons| Length | Width | Height | weight. totals at the end)
7a. Approximate value (just guess an approximate value.
7b. name your list USED HOUSEHOLD RELOCATION GOODS (to avoid a high customs duty amount)
8. Seal all openings (preferably with adhesive tape
9. Every carton should have your postal address in the country of origin and also the address in Cambodia)
10. A copy of the address to be inserted into EACH carton
11. Avoid ANY TYPE OF DANGEROUS GOODS (flammable or inflammable substances. food items, alcohol etc.
12. Make a list of freight movers (freight forwarders) and their email addresses
13. Request a quotation from them all by sending them an email (use the BCC field so that each freight forwarder gets his individual email without knowing who the competitors are
14. attach the packing list and the list containing only the dimensions
15. Tell the freight forwarder the following
    1. an approximate date for pick up (this is NOT a commitment) you are only giving them an idea about WHEN
    2. an approximate date you want the freight to be in Cambodia. Please add about TWO WEEKS more to the
      date of your actual arrival. Because: if the freight arrives earlier and is in port, you will pay a DEMURRAGE fee
      (this is usually per kg per day multiplied by the number of days. Holidays mean nothing!! and demurrage fees
      can (probably) burn your bank!!
   3. You should ask for a COMPLETE list of prices without any hidden charges
   4. Ask them also to quote for DOOR DELIVERY
   5. Ask them to quote for CUSTOMS CLEARANCE
   6. If you want an insurance cover (transport insurance), inform them. But FIRST talk to an insurance company
     what they would charge!! Do not commit without knowing the amounts. Transport insurance will be covered
     only if you tell the freight forwarder in writing
16. You need to have ALL the contact details of the freight agent in Cambodia
    Agent name (company)
    postal address
    Telephone number (alternative numbers. not just a single number)
    email addresses
Remember you might get a quotation mentioning w/m (weight measure). Don't panic!
1. note down the Total weight of all your pieces
2. calculate the volume of your freight :
  volume = number of pieces x Length x Width x Height
  eg: you have 1 carton with 0.60 m x 0.60 m x 0.60 m weighing 15 Kg
  Volume = 0.60 mx0.60 mx0.60 m = 0.216 cubic meters.
  If the freight forwarder uses 1:6 weight volume ratio (1000/6) : 0.216 cubic meters x 166.66666 = 35.9 kg
  If the freight forwarder uses 1:5 weight volume ratio (1000/5) : 0.216 cubic meters x 200 = 43.2 Kg
  The actual weight of the carton = 15 Kg The volume weight: either 36 Kg (rounded up) or 43.5 kg )rounded up)
  The higher weight number will be used for your freight charges!!
Remember to keep copies of all your documents on your computer AND also send it to your own email address, so that you can access the documents when you are in Cambodia.
Once you have chosen the freight forwarder and entrusted them with the responsibility of moving your freight, ask them to keep you informed via email, regarding the progress. They should tell you
1. The shipping line
2. The name of the ship
3. sailing date and ETD and ETA (Estimated Date of Departure and Estimated Date of Arrival)
Hope you don't feel groggy after reading all that.
If you need any help, please post. If I can help you, I shall. If I cannot, I shall honestly tell you, I cannot.
wish you all the best
Cheers
Suren