how to normalize CNN-Data?

I got always NaN as output from my network and it might be possible that the network parameters diverge during training. Could somebody help me to fix this problem? This is my code:

X(:,:,3,60) = rand(500);

Y=randn(1,1,250000,60);

layers = [...

imageInputLayer([500 500 3])

convolution2dLayer(51,6)

batchNormalizationLayer

reluLayer

maxPooling2dLayer(2,'Stride',2)

convolution2dLayer(20,9)

batchNormalizationLayer

reluLayer

maxPooling2dLayer(2,'Stride',2)

convolution2dLayer(10,12)

batchNormalizationLayer

reluLayer

maxPooling2dLayer(2,'Stride',2)

convolution2dLayer(6,12)

batchNormalizationLayer

reluLayer

maxPooling2dLayer(2,'Stride',2)

batchNormalizationLayer

convolution2dLayer(6,12)

reluLayer

maxPooling2dLayer(2,'Stride',2)

fullyConnectedLayer(250000)

regressionLayer;

];

options = trainingOptions('sgdm','InitialLearnRate',0.001, ...

'MiniBatchSize',miniBatchSize, ...

'MaxEpochs',15,'ExecutionEnvironment','cpu');

net = trainNetwork(X,Y,layers,options);