A workable reed should normally have contours like this with the thinnest part of the blade at the tip & the sides while thickest is in the centre and the back:-
                                                  
Play low D moderately softly. If you have some difficulty doing this chances are the tip of the reed is too thick. In this case, scrape in this area, being careful not to take too much cane off too quickly:-
                                                    

The response of the low register can also be improved by scraping the sides of the reed at the back:-
                                                  

Take the reed off the crook and blow the reed reasonably strongly. On a well-adjusted reed, it should be possible to produce two “crows”; one normal crow and one crow that is at a lower pitch. The ease with which this lower crow speaks, is an indication of how responsive the reed will be on the instrument. If a reed on the instrument makes a stuffy sound, try lightly scraping in this area to improve the general response:-
                                                    

Play a crescendo to FFF on middle F & E. If the sound drops suddenly in the louder dynamics this means that the reed is too thin towards the tip. It should be noted though that it is often a good thing with a new reed to have the situation where the sounds drops a little, in the louder dynamics as this is an indication of a flexible reed. After playing the reed for about a week the cane should stiffen up and this “problem” will go away leaving a great flexible reed. If this situation is causing problems after a week's playing, cut back the tip of the reed:-
                                                    
 

If a reed is too buzzy is can normally be caused by a couple of situations:-

• the wires are too loose or
• the reed is too thin towards the tip compared to the thickness of the back of the reed.

A good general rule is to avoid taking cane off the centre back of the reed, however this assumes that the thickness of that area was correct to start with. Sometimes, scraping in this area is the solution to a reed that refuses to improve by all other means:-
                                                   

Wires should be reasonably tight and generally oval in shape. Loose wires can produce a reed that is unstable in performance and can react more unfavourable in different climatic conditions..
 

Squeezing the front wire at the sides put more strength in the blade that can result in a louder dynamic range. Squeezing the second wire in the middle can produce similar effects. Squeezing the first wire in the middle or the second wire at the sides closes the tip opening and results in a smaller dynamic range.
 

A new reed will harden up in the first week of playing. A light scrape in the middle of the reed should restore the flexibility that may have been present when it was first played:-
                                                     

A reed that has been played for a number of weeks will start to build up grime on the outside and inside of the blades. This in turn influences the response. Lightly scrape over the entire surface of the reed. Then, after soaking the reed for ten minutes, carefully push a pipe-cleaner from the back of the reed through the tip of the reed moving it slowly from side to side. This should restore the performance of the reed somewhat back to how the reed played after the first week of playing. The differing factor here is the gradual deterioration of the cane the more it is used.
 

Do not over soak your reed before you play you instrument. A reed should not be waterlogged. Anything from twenty seconds up to five minutes should be enough. If a reed is not ready to play after a couple of minutes in water, then it needs further adjustment to improve its response.