Two questions: 1) Where does the water come from? And, 2) Where else could you send it?
First thought is that you may need to do some grading and/or install some sort of french drain system to help that water run off to somewhere else... or perhaps intercept it before it gets 'cornered' if possible. Also, those edgings around the patio appear to stand a bit above the level of the patio itself... if I'm seeing that right that can't be helping.
Hard to say much more without a broader sense of the lay of the land. Again, the water needs to go somewhere, and that's the first decision.
far as the low spots in the patio themselves that may just be the result of some settling if the material beneath wasn't perfectly compacted. So you might pull up the low-lying bricks and tamp in some additional sand to get those spots up to grade. You might also consider a narrow gutter around the edge to catch water and direct it somewhere away from your wall. Again, much depends on the overall grading of your lot.
Blue, or blueish-purple (ie, at a slight angle so it's away from both the house and garage, but closer to blue.) You want to get the water away from the building, not funnel it alongside the building.
Responding to comment: developing a grade is a "simple-yet-tedious" process, for the most part. My preferred method is to set some stakes 3-4 feet tall, mark them all with a level (laser these days, dumpy or transit or water or... in the past), and then mark a line on each, depending where it is, at some fixed distance above the desired grade - say 30" above. Then I run strings, tightly, between those marks, and mark my rake and/or tamper handle at 30" - it's then a simple matter to line up the strings (to form a plane floating 30" above grade) and see if the rake or tamper is too high (mark above) too low (mark below) or right on (mark even with) when set on the surface at any given spot. For convenience the plane should not be too low (or it's a lot of bending to see if things line up) nor too high (it's difficult to get stakes well-anchored for a taught string when the string is 5 feet up the stake.)
You could set something to screed on by adapting the same method - I don't recommend screeding for a sand base - it needs to be well compacted, or it will shift, so screeding it doesn't really do anything much to develop the base you need, IME.
In either case "sloping two ways" is a simple operation of referencing an imaginary LEVEL plane & subtracting for the position in both X and Y before making the mark on the post or setting the plank, pipe, or whatever you'd be using to guide your screed on the non-level plane you are creating.
For a concrete example, suppose we slope 1/8" per foot in blue and 1/32" per foot on red. The high corner is where the garage and house meet. The outside corner by the garage is dropped 1.83 inches. The house side of the end away from the garage is dropped 1.09 inches, and the outside corner at that end is dropped 1.09 + 1.83 inches. Any spot in the middle can have a precise elevation computed, and then you do your best to approximate that in practice, and don't sweat 0.05" too much. For the sake of simplicity and sanity in measuring you can set your grade stakes on an 8 foot grid, for instance, rather than "right at the edge of the patio" and you can actually set a row beyond that if it makes it easier to "see the plane" while working.
Best Answer
Stake out the four corners. Find a way to mark each stake at the same height. A laser level would be easiest. If you don't have one of those, you can get string-line levels that hang from a string between each stake.
Once you have 4 level marks, you can now figure where the mark should be on the high end. Figure out where you want the top of the patio to be, then subtract the height of the brick. This will be where the sand base has to come up to. Now measure from that point to the original level mark you made. Let's say that's 4".
Now figure out the slope you need for the two adjoining corners. Most say you want the slop to be 1/8 - 1/4" per foot.
So if this is a 10' patio, and we want 1/4" per foot, that'd be a total slope of 2.5". Mark these two corners at 6.5" below your level mark. (4 + 2.5).
Now for the last corner (opposite the first) we'd mark that at 9" below level (6.5 + 2.5).
You now have the 4 corners marked at the proper slope.
After you get your grave base compacted, bring in the sand, and put down screed guides to line up with each of these points. I like using conduit for this. Not too pricey and comes in long lengths. Lay your screed on these as you go along to keep a consistent slope to the sand base.
Now, with this example, the outside edge of the patio is 9" lower than the high end of the wall. That's a pretty big difference. You may want to stick with a 1/8" slope (at least along the direction parallel to the house) but either way, keep in mind that height difference before laying the patio so that the outside edges are still above grade to allow full water run-off.