Ok here goes..... DEPENDING on what you are rendering over brick/ lathes and where abouts on the building the rendering is ...... it can be done in 2-3 coat work the mix stays the same 2 h/lime to 1 sand.
1st coat 2 hydrulic lime either 5.0 or 3.5 Â to 1 sharp washed sand add 3-4 bundles of hair per 2 barrow load mixer or 2 bundles if you are using a small mixer , mix for around 20 mins adding water slowly when you think its ready switch off the mixer and let stand for 5-10 mins then remix and use . Damp the substrate do not soak apply render to 10mm thickness and scratch in a daimond patten and protect from weather damp hessian is good for this leave for around 5/7 days depending on the weather.
2nd coat pretty much the same as coat one but use weaker lime 3.5 if you have used 5.0 on the 1 st coat and you can add soft washed sand to the sharp 50/50 also if you need to you can rule off and fill in the 2nd coat, only give the 1st coat a light spray/ mist  of water before appling the second coat again leave for up to a week.
3rd coat (top coat ) use hydrulic 2.0 again 2-1 but this time use soft wash sand ( no hair ) do not rule off just use a wood grain float to finish again protect from weather for 2 days, after 24 hrs cheack render for hair line cracks remove with a light spray of water and float  after 48 hrs do not work on render anymore. Hope this helps