I have copied an earlier answer to this question for you by Spritz.
"If you haven't been pruning your Laburnum in previous years, you can only really cut out the dead wood now. My RHS book gives advice on how to train young trees in their first to fourth years. It says that any pruning should be done in late summer to before mid-winter to avoid the sap bleeding. It also warns aginst renovation pruning into living wood "as this will breach the tree's natural defences" sorry, but I am quoting a reputable source of information!".

how about a please or thank you Guest. this is a garden forum site and we are all normal people sharing our hobbies/interests. :o)

And we can't post images including diagrams as replies to a post! Guest do a Google search on pruning a laburnum you will find lots of info...

Most guests come to this site following a google and nobody ever says please when googling, you try and keep the words to a minimum to ensure you are not faced with 1000's of irrelevant contacts and as Mg has already pointed out guests can not say thank you after getting an answer. All we can hope for is that having been given a civil response to their question they will return as members instead of guests. It can take some of us longer to get a handle on the protocol to follow and sometimes we forget to press submit or press the wrong button.

if they come to this site they have to retype their question so i dont see why they cant show some 'manners' ,, it is clear from the blurb that we are a social site.

I agree SBG