Andy
I had a trio family 850 up to a couple of years ago and found it eazy peezy to put up. A damn site easier than my current Isabella.
If yours is the same pole arrangement as mine try the following
Lay the poles out on the ground at the side of the van.If you look closely the pole ends should be numbered, the same number fits together.
1 You will have 3 "half length" poles with a hook on one end, these fasten into the eyes on the van buffers that stretch the awning against the van. place one at each side and one in the middle of the van.
2 There are three tubes that fit into the ones above to support the front uprights and the cross members. Two are the same, these go at the sides of the awning and the one that is slightly different (more short tubes sticking out of it) goes in the middle.Lock them in place with the screw fitting.
3 The front outer uprights are made up of two sections that extend on "notches" the center upright is made up of 3 sections with the bottom one adjustable on notches also. lay these out at each front corner of the awning and in the middle.
4 The front cross members are each made up of 2 sections these are usually fastened together with a spring steel clip and wire. lay these out accross the front of the awning.The top sections of the uprights may also have wire fastenings holding them together.
5 The 3 short tubes with hooks, support the front canopy.
Once you have laid the poles out on the floor and they look ok or actually erect the awning, I suggest that you get a pack of different coloured insulation tape and colour code the various jounts.
Note that it is easier to erect the awning if you unzip all of the removable panels first and just put the roof onto the van first with the poles in place, then refit the 4 panels, two front and one each side.
Hope this helps
Alan