The photos show me planning a laminated workbench top made from Mountain Ash, which is a fairly dense wood and  like most eucalyptus varieties it can be difficult to plane (without tearout) due to its irregular grain.   And being laminated the grain direction of each piece is not all the same way which also complicates planing the surface without the dreaded tearout.  I am not going to cover how to glue pieces of wood together to make a large wood surface but I will make the comment that; the flatter you can get the surface by accurately joining the pieces together the less work there is in planing the surface perfectly flat. For more information on jointing boards go to   jointing long boards.

Once you have your surface glued up and cut to size you will need to put it on a flat surface to plane it flat.   I find the best thing to do here is to fix your top to the table frame it is  meant for.   Other than that you will need to put it on a flat workbench, which also works well as long as you can secure it without any clamps protruding above the surface as the plane will surely hit them.   Bench stops are best if you are going to do it this way. 

To begin with, start planing across the surface as shown in the top photo, using a trying/jointer plane.   As you can see from the photo the plane will take off the high spots until you have planed it flat.   I prefer to plane directly across the grain as opposed to planing across the surface at 45 degrees as I have found there is a lot  less chance of tearout particularly on irregular grained woods.  The key here is to set the depth of cut fairly coarse so you can remove a lot of wood quickly but not so deep that you will cause deep tearout.   A little shallow tearout at this stage is acceptable because the next planing phase will clean it up.

Still using the trying plane, but with the blade set a lot finer, the next stage requires you to plane the full length of the table to get it flat in its length.  A long straight edge is handy here to get an idea of the high spots. A word of caution, only use your straight edge if you know it is straight, most pressed metal rulers you buy are not very straight. If you don't have a good straight edge you will need to rely on the trying plane to remove the high spots.  If there are any significant high spots mark them out with a pencil so you can start on them.   In most cases you will find the surface will be pretty straight in its length if: you have dressed your boards straight, your joinery is reasonable and the frame the top is sitting on is straight.

 The second photo shows me pushing the trying plane from one end of the top reaching out as far as possible and stopping halfway down the length of the top.  To do this start from one edge of the table top overlapping your cuts as you work you way across the surface to the other edge.  So in essence you have now planed level half the top.  The third photo shows how I have gone down the other end of the table top, reached out to overlap where I stopped the cut from the other end.  Now pulling the plane toward me I can level the other end of the top.  In the same fashion as before, I start on one edge and work my way across the top with overlapping cuts to the other edge.   It is important at this stage to ensure you are taking a nice even shaving on each cut so that you maintain the flatness of the top across its width.  The depth of cut at this stage is a judgment call and will vary with different woods. The thing to avoid at this stage is deep tearout, so I always err on the side of caution and prefer to make more finer cuts to avoid tearout, rather than coarser cuts thinking you will save time.  As my experience tells me deep tearout now will cost me a lot of time to plane it out.   If you are getting tearout with a fine cut and your blade is sharp you will be better off converting the plane to a scraper and scraping the top rather than planing it.  I did this with a teak bench top and it worked out fine.  Took a bit longer but I didn't get any tearout.  You will probably need to go over the top in this way several time to get it flat.

The last stage is to finish off with a smoothing plane set very fine.   In the same way you pushed and pulled the trying plane before, go over the table top with the smoothing plane until you  are satisfied with the result. As you can see from the fourth photo, when you are getting close to a finished product you will be getting full length shavings, the surface will start to shine and the surface will be very smooth to touch.  The first time this top felt sandpaper was after the first coat of finish where I gave it a light sand with 800 grit paper prior to the final coat.

The last photo shows the result of an afternoons work.

A couple of notes to think about:

Don't use a skew action when planing as this may induce tearout on some timbers.

Keep the table top clear of shaving as you work to ensure nice even cuts with the plane.