Another tip. Some may want to fill some of the trench with open graded stone, but wrap it with a filter fabric. Sure that will work. go ahead. In the narrow trench you are digging getting the fabric in right, filling with stone and then getting a lap will be a real job. Then suppose the sides cave in before the lap is there. All in all it's a bitch of job and more time and labor intensive, besides being undependable. If suppose there is a little cave in for the method I describe and the pipe is accidentally laid on some cave-in. Short of some digging by hand, that hump in the line is not highly critical because the water in the pipe can exit via the slots and fabric to the porous and backfill and then re-enter down the line. Of course it is best not to have that.
Before anything is done do a simple survey of elevations around the site. If you have access to a surveying level or transit, that is fine. However, Take a carpenter's level and hold it at a fixed place on a support, such as a section of 2 x 4. Have a helper out there with a tape. Sight to him, keeping the level level. Record the height of the level above where you are standing, as well as the place on the tape out there as height above the ground. With a series of these shots you can get ground elevation differences from the "instrument" to the guy out there and then develop p a map showing elevations above a fixed place. Then laying out the drain you want at a slope of say 1/8" per foot, you can show on the map how deep you have to dig at each location. Actually even if you lay the pipe level, gravity will move the water toward an outlet. A slight slope is better.
I have found that it is not usually possible to dig a trench and lay a drain pipe into a area and expect water to flow to it from each side. Yes there will be drainage that way, but it is undependable. It is much better to cut off the flow from outside.
To check on what you are doing, before anything is done, with a post hole digger install some observation walls at critical places, such as along side the house on ALL SIDES.
These can be downspout pipes, slotted some near the bottom. Use a measuring tape and record water levels. Keep a record of the water ELEVATIONS in each pipe before and after the work. You may want to add more drains if you find not everything is perfect. For instances, in some areas water sneaks under the pipe and rises beyond. If that is a basement, you don't want that.
By the way, sealing leaks in a basement wall is just asking for trouble. If you then stop the release of water pressure from outside the wall by that sealing, you stand the chance of having the wall cave in due to added pressure out there.