Signs often disappear as you pass through cities/towns though.
Often only local route numbers are signed, even though these use the same LF1 path which can be confusing at first.
Also, I found the Dutch cycleways quite slow going. I planed 100 miles per day which turned out to be too much even though that's okay for me in the UK - my average speed was down due to constant route checking, navigating tight turns, bumpy surfaces, dodging slow moving bicycles......etc
which will show you the knooppunten numbering system along your route. Press on the "LF en knooppunten" button and it shows you where all the markers are. I just made a long list of the numbers and went from marker to marker. The LF1 can get quite windy so you might find you are a bit slower than you expected, even though it's pretty flat on the bit that I did. As @e-rider mentioned, you have to be eagle-eyed to stick to the route in towns.
Also have done most of that route, as others have said, we did Hook to Alkmaar on our first day, we did over 80 miles including a diversion to Delft. The quickest bit was travelling through the dunes where progress was rapid, until that is we reached a village where the signs disappeared. You have to be alert to spotting them, no rhyme or reason as to their placement, having now done over 2000km in the Netherlands it's a lot easier but even now we occasionally get caught out. Enjoy
We did is South to north and used this book http://www.esterbauer.com/db_detail.php?buecher_code=NORD1
If you can read a map in your bar bag whiulst cycling (its a skill, but easy enough) then we found it a lot easier to follow the map than the 'mushrooms'
The book comes with a free GPS download for those so inclined
We did the bit from Hoek northward to Ijmuiden (and on northwards over the Afsluitdijk) on our way to Norway. It's a good stretch, especially through the dunes and forest once you're out of the urban sprawl of Rotterdam-ish. You pass a number of seaside towns and it would be nice to take the time to pause, eat ice creams and pannencoeken and do the tourist thing a bit.
Some of the ferries are free for bikes, but not for cars. Don't assume you need a ticket; if you can't read the information, ask someone. (We bought an unnecessary ticket before we realised). Everyone will be happy to show off their English and even those who are a bit shy about it will be able to help.