Use Diamene: https://www.google.com/amp/s/www.graphene-info.com/new-graphene-material-called-diamene-switches-flexible-harder-diamond-upon-impact%3famp
It is light, malleable and wearable but once something hits it becomes extremely hard. Use a few hundred layers that are inlaid into a spidersilk-like substance as such substances are also light, malleable and extremely durable. This helps keep the fragments of Graphene (if there are some) to stay in place, since Graphene's edges are very sharp you dont want it to be flying about. The top layer being spidersilk also helps spread the impact a little before it reaches the Graphene.
To make the most of these layers, you first have the spidersilk at the top. Spidersilk is used instead of Kevlar because it's much stronger (1, 2, mentions it can be 10 times stronger than Kevlar, 520 MJ /M3). Then you have alternating layters of diamene and Carbon Nanotubes (https://en.wikipedia.org/wiki/Carbon_nanotube) with a last layer of spidersilk finishing it off again. These are thinner than spidersilk allowing more layers of diamene and they provide the same lightweight, flexibility, support and strength while seperating the diamene layers from each other. Better yet, the optimal size of a CNT can fit another CNT inside which is slightly less strong but it would add to the total strength. With a couple of hundred of these layers you are sure to stop several .50 BMG shots. Which leaves the kinetic energy to be disposed off:
You could augment this with non-newtonian fluids (https://en.m.wikipedia.org/wiki/Liquid_Armor), but in this case the fluids would only function as shock absorbers to reduce the kinetic impact before it reaches the body. But I would use a different method, mainly that of wheels. When a wheel hits something the metal frame is protected by the air in the rubber wheel (amongst other things). This impact causes an increase in pressure of the air and this is evenly divided over the wheel's frame. The armor would carry a liquid (probably an oil) that absorbs a lot of kinetic energy when it is pressurized. This is worn as a middle/bottom layer which rests on a frame. Whenever a bullet impacts the armour a portion of the energy is absorbed, turned into pressure and evenly divided over the frame so the pressure doesnt squeeze the user. It will never soak up the full kinetic force, but it will definitely spread the force even more than the other layers and absorb some to boot.
1: https://openi.nlm.nih.gov/detailedresult.php?img=PMC2939878_pone.0011234.g004&req=4
2: https://en.wikipedia.org/wiki/Darwin%27s_bark_spider