Clock faces are complicated things carrying a variety of information. I have found a successful approach is to produce two clock faces out of cardboard; one has a long minute hand and dashes for minutes around the edge, the other has a short hour hand with the numbers 1-12 around its edge. This separates the numbers from the minute hand. First you need a memory tab to denote the role of each hand. The minute hand is long: the word minute is long. Starting with the minute hand clock (which has no numbers around the edge), practise moving the hand in a clockwise direction, drawing a coloured arrow (colour is more significant that plain black) onto the clock face.
The minute hand goes around the clock quite quickly. In the time it takes to brush your teeth, it will have already moved past five of the dashes marked around the edge. In the time it takes to watch Neighbours it will have moved on even further. Practise moving the hand round, getting the child to count how many dashes past the top that the hand has moved eg fourteen minutes past, twenty one minutes past, thirty seven minutes past, fifty minutes past etc. FORGET all mention of quarter past/to etc (these are unnecessarily confusing). Do not rush the child into counting in fives, let them count the dashes each time from one in order to reinforce the lesson: the minute hand moves round in one direction, the dashes alone denote the number of minutes past.
Then move onto the second clock face. This has a short hour hand (the word hour is short). 'The hour hand is moving so slowly it has time to notice the numbers around the clock's edge' (the numbers ONLY relate to hours). Now practise moving the hand around (add a coloured arrow to denote direction). In the time it takes to brush your teeth, it will have moved a little way. In the time it takes to watch Neighbours, it will still have hardly moved at all. Relate different activities to the movement of the hand, relating the numbers to activities in the day eg 1 o'clock in the morning: middle of night, most people asleep except perhaps the milkman and doctor etc.... through to midday.
Then 1 o'clock in the afternoon; people finishing lunch, cat fast asleep, teachers having cup of tea before afternoon lessons begin etc. Having introduced minutes and hours COMPLETELY SEPARATELY, the child is better equipped to handling the two being put together although to start with, place the two faces side by side and position them to display '4 minutes past 6 o'clock', '41 minutes past 10 o'clock'. Then put the two hands on the hour clock making sure you have dashes between the numbers. The child is now able to tell the time from an analogue clock.
By keeping the format of expression consistent: x number of minutes past y o'clock, the overloading due to variation of expression (eg 20 minutes to 7 o'clock, quarter past three etc) are removed. The initial introduction of separate minute and hour hand removes confusion of minute hand and numbers around the clock's edge, and the prompts of 'long hand = long word minute', 'short hand = short word hour' are accessible to remind the child if they subsequently forget which is which. For dyslexic children who find telling the time a difficult task, keep to the x minutes past y o'clock expression for some period of weeks during which time constantly use and practice the usefullness of reading the clock.
Only much later introduce alternative methods of expression (quarter past etc)...they will only be able to assimilate this information if they thoroughly understand the spatial display.
When using a digital display (which is everywhere these days), the 'x minutes past y o'clock' terminology is very easy to identify (except that the minutes are displayed after the hours, so explain this clearly). 4:18 = 18 minutes past 4 o'clock.
When moving onto the twenty four hour clock, relate the hours to real activities and practise subtracting 12 from such numbers as 14, 21 etc. to help them become familiar with this necessary skill Sally Raymond.