4 And pillow was my helmet fair displayed;

displayed > spread out (presumably his head was resting on the "bunch of haires" mentioned at 107.32:2, and "helmet" should thus be read as "helm" or "crest"; but cf. 304.53:9)

5 While every sense the humour sweet embayed,

humour > dew [of sleep: cf. 101.36:2] embayed > bathed

6 And, slumbering soft, my heart did steal away; 7 Me seemed by my side a royal maid

Me seemed > [It seemed to me that]

8 Her dainty limbs full softly down did lay:

dainty > delightful, comely full > very, exceedingly

9 So fair a creature yet saw never sunny day.

109.14