print tuning on geeetech i3 pro b

[das998]

I cant quite get my printer to work, slicer i use is cura slicer on repetier host, 0.4 nozzle diameter at 220 with the bed at 64, using pla filament, layers are inconsistent and sometimes thin out during the print, they also dont quite combine smoothly either, retraction settings are at 3.6mm, any help or ideas would be really appreciated