What is the correct way to create REST web services?

I have the following state machine, and I want this:

• create a new order
• add elements to it (list is optional)
• confirm the order, causing completion
• pay for it
• send him

And this thread is controlled through the REST web service, and I'm not sure which method follows REST principles better.

I came up with two possibilities (the numbers below correspond to the numbers above):

first operation - set by

1. 
POST /create HTTP/1.1

2. 
POST /addItem HTTP/1.1
<data>
    <itemId>123</itemId>
</data>

GET /listItems HTTP/1.1

3.
POST /finish HTTP/1.1

4. 
POST /pay HTTP/1.1
<data>
    <price>123</price>
</data>

5. 
POST /send HTTP/1.1    

second operation - set in the body

1. 
POST / HTTP/1.1
<data>
    <operation>create.new.order</operation>
</data>
- returns resId

2. 
PUT /{resId} HTTP/1.1
<data>
    <itemId>123</itemId>
</data>

GET /items HTTP/1.1

3.
PUT /{resId} HTTP/1.1
<data>
    <operation>finish.order</operation>
</data>

4. 
PUT /{resId} HTTP/1.1
<data>
    <price>123</price>
    <operation>pay.order</operation>
</data>

5. 
PUT /{resId} HTTP/1.1    
<data>
    <operation>send.order</operation>
</data>

The second solution seems better, but I don’t know if I can indicate the operation in the request body - is this normal or not?

Also, I am not sure whether to use PUTeither POSTin 3and 5in the second solution, because I really do not update the resource, I just change the state of the state machine.

, ?